Llansadwrn (Anglesey) Weather Diary 2010

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January 2010

1st: Snow covered mountains set the scene for the New Year. There was clear sky earlier with overnight air minimum of -1.1C and -4.5C on the frosty ground with a sprinkling of snow pellets. Pressure was 1008 mb and there was a light N-NNE'ly breeze and visibility was very good. A little cloud had developed by 09 GMT this increasing through the morning and by 14 GMT the sky was mostly cloudy as a narrow band of showery precipitation moved across. There was a shower of rain here, but snow was falling across the mountains where snow was lying at 600 ft on northern slopes. There was a moderate shower of snow pellets at 1745 GMT that covered the ground, later there were fine snow crystals and some flakes leaving a slight crispy covering. [Pptn 1.1 mm; Max 4.3C; Min -1.0C; Grass -4.5C]
2nd: The sky was clear after midnight with a bright Moon. In the morning the grass minimum thermometer had recorded -4.8C while the air minimum was more modest at -1.3C. Visibility was only moderate in smoke haze so that the mountains were mostly obscured. Pressure was 1016 mb in a general low-pressure area over the UK with several shower troughs shown on the charts. The ground was frosty with snow pellets and a little sprinkled snow here and there. Some sunshine at first then with cloud encroaching and a rising temperature there was rain before noon. A band of precipitation was moving South and falling mostly as snow in Manchester and Cheshire. There was 30 minutes of rain from 1430 GMT turning to moderate small ice pellets at 1445 GMT. Snow was falling on the mountains as low as 400 ft with moderate accumulations above 2500 ft. During the evening rain turned to sleet and small flaked snow by 2230 GMT. [Pptn 1.5 mm; Max 3.8C; Min -1.3C; Grass -4.8C]
3rd: Snow cover on the mountains was at 400 ft, or less, in the east of the range, but 1000 ft in the West. Mostly thin at lower levels with good amounts accumulating over 800 ft. There was ice to low levels in most places. A beautiful winter morning with an almost clear sky at 09 GMT; woodpeckers were drumming and there were buzzards calling in the vicinity with a raven croaking from its perch on the tallest tree. Buzzards and ravens don't get on, no doubt it was keeping an eye on how close the buzzards would risk coming. There were some icy deposits including a few snow pellets and frost on the ground (no hoar), particularly in shady areas and water was frozen in the bird's supply that I would replenish with lukewarm after completing the obs. Supplying water in this sort of weather is good for the birds as well as topping up the feeding stations. The soil surface was hard, but not yet frozen just 0.3C at 5 cm depth. The temperature at 30 cm had fallen to 2.4C and to 5.8C at 100 cm. The day was sunny and there was a deep orange sunset and peach twilight with another cold night to come [Pptn 0.0 mm; Max 1.6C; Min -1.8C; Grass -4.3C]
4th: Clear sky overnight with an air minimum of -4.2C and -7.4C on the grass. The temperature of the frozen soil surface at 5 cm depth had fallen to -0.5C and to 2.0C at 30 cm, but it was still 5.9C at 100 cm. With the sun rising above the Carneddau Mountains at 0858 GMT it was a sunny morning. There was slight hoar frost and riming on the knife-edge of the copper raingauge, otherwise it was frost on frozen dew with a deposition of 0.24 mm recorded by the drosometer. Pressure was 1024 mb with high-pressure over Wales and S Ireland, a ridge from Greenland-high 1044 mb. A cold front over the N of Scotland was beginning to move S. Pressure was low over the Gibraltar Strait with Atlantic-low 996 off Portugal; the jetstream currently is, and has been, well South. There was little change in the snow and with overnight temperatures in places down to at least -6C there was frost and ice at low levels persisting in valley bottoms and shaded slopes. The slopes of Carnedd Llewelyn were well covered and there was a covering of snow along the A5 at Llyn Ogwen (above left) that was partially frozen. Three rocky peaks of Snowdon, Yr Wyddfa, Crib Goch and Crib y ddysgl viewed from near the partially frozen Llynnau Mymbyr looked brilliantly white in afternoon sunshine (right). In the Llanberis Pass snow was sparse along the road below 1000 ft, but icicles were frequent and waterfalls frozen sheets of ice. There was little water in the enlarged Llyn Peris at the foot of Elidir Fach used as a reservoir by the Dinorwig Power Station commissioned in 1984. Most of the water was pumped up to Marchlyn Mawr reservoir (off peak) to be used to generate electricity at time of peak demand later in the day. Dinorwig's reversible pump/turbines are capable of reaching maximum power generation in less than 16 seconds and is the largest station of its kind in Europe. Cloud began to encroach from the West by 1500 GMT; during the evening there was intermittent light deposition of snow crystals here as showers moving S skirted the E and W coasts of the island. [Pptn 2.2 mm; Max 3.8C; Min -4.2C; Grass -7.4C]
5th: Ice precipitation between 03 and 0445 GMT, as the cold front moved S over the Irish Sea, left a covering of 0.5 cm on the ground in the morning. At 09 GMT there were 6 oktas cloud cover and slight precipitation of snow and very small (1- 2 mm) conical snow pellets in a temperature of -0.4C (dewpoint -0.7C). With cloud cover (cumulus and cumulonimbus) it had been a 'little warmer' overnight so that the ground was softer and the temperature of the soil at 5 cm had risen to zero. Temperatures lower in the profile continued to fall being 1.8C at 30 cm and 5.7C at 100 cm. Further showers of snow pellets (larger) from 0940 GMT through the morning with prolonged snow showers from 1105 GMT. By noon there was snow to low levels including on the beach at Rhosneiger on the high tide mark. Schools began closing early as snow-covered roads became difficult in outlying areas of Anglesey and Gwynedd. A wave on an occluded front developing over the Irish Sea (low 1003 mb Liverpool Bay) began moving S bringing more snow in the afternoon and later to many southern parts of the UK. The Meteosat MSG image at noon shows the swirl of cloud over North Wales associated with developing system. [Pptn 2.8 mm; Max 2.0C; Min -3.0C; Grass -5.5C]
6th: In the morning there was 3 cm snow lying at the weather station at 300 ft and below including the shore at Rhosneiger, but it had gone from the sand. Mostly cloudy with cumulus clouds in the vicinity, but breaks slowly appeared through the morning with some sunny spells developing. The temperature of the Irish Sea, that has been above 10C, has fallen and was 9.9C today. Snow and snow pellet showers continued over the mountains, mostly on the western part of the range. There was a force 2/3 NE'ly breeze in the evening with slight showers of snow pellets and snow crystals continuing late. [Pptn 0.1 mm; Max 2.0C; Min -0.4C; Grass -2.8C]
7th: Another crisp morning with an overnight air minimum of -1.5C, but it was -5.2C above the lying snow. In Chorlton in Manchester the air temperature had fallen to -9.6C. A mostly cloudy beginning with much cirrus clouds overhead and cumulus clouds with cumulonimbus on the horizon far in the West. Enough snow still, about 2.5 cm, for snow lying that must cover 50%, or more, of the ground surface excluding roads, buildings and trees and rocks. Most of the UK would have no difficulty in recording lying snow, some parts of the coast and S-facing sloping fields were loosing cover, but many fields in S and central Anglesey were sufficiently covered. Most main roads were clear, but many minor roads had not been treated and remained icy. A sunny day with very good visibility giving good vistas of the snow covered mountains . These changed through the day, as the sun moved around casting moving shadows across the cliffs on the north faces. Towards evening the bright white and dark shadows turning pink as the sun began to set. The MODIS TERRA satellite image left using bands 7-2-1 that depict snow as blue against the green land surface shows the almost blanket cover of snow over North Wales. This image using true colour bands covers the UK and is the one used widely by the Press and TV, it is rare not only because of the extensive snow cover, but also because it was relatively free of clouds. Under a bright starry sky with little or no wind temperatures were soon falling. [Pptn 0.0 mm; Max 2.0C; Min -1.5C; Grass -5.2C]
8th: An almost clear sky morning, just a little appearing around the mountaintops and on horizons to the far NE and W. The ground thermometer placed just above the snow had fallen to -8.4C and the air minimum to -3.3C. The remaining snow, still enough to record lying snow, was crisp underfoot and little changed in depth at 2.5 cm. Under the blanket of snow the temperature in the soil at 5 cm was unchanged at 0.0C, recovering from -0.5C on the 4th, but falling in the profile to 1.7C at 30 cm and 5.1C at 100 cm. In the wood where there was little snow the bare ground is hardening up, but the leaf layer, being disturbed by blackbirds and thrushes finding food, is softer. Pressure 1027 mb was rising with high 1030 mb developing over Scotland. A sunny day with smoke haze increasing so that the views of the mountains and Lleyn were not as clear today. There is no sign of any snowdrops, they are poking through as are some early daffodils, but not developing. I did find 2 or 3 winter heliotropes out in flower in a sunny spot. The sun set as an orange ball across snow covered fields at 1610 GMT (that's 7h 12 minutes sunshine today). The evening was mostly clear, windier force 2/3 and the air temperature had risen above freezing at 2200 GMT. [Pptn tr; Max 1.4C; Min -3.3C; Grass -8.4C]
9th: An almost clear sky at 09 GMT, there were a few cumulus clouds, some towering, far to the NE over Liverpool Bay. Earlier, between 0645 and 08 GMT, there had been falls of small snow pellets and very small star-like ice crystals most about 1 mm, or less, a few larger ones were rimed but no more than 2 mm, all of which were still on the ground and other surfaces including the Stevenson screen roof and frozen water ice. Two curlews flew over calling out and the woodpeckers were drumming, they seem to drum about this time, but I don't hear them later at this time of year. Snow was still lying on the ground around the weather station, about 2 cm, looking very little different to yesterday with adjacent fields a little less in some patches. The soil temperature, with a covering of snow, had fallen to -0.3C and was 0.2C at 10 cm. A mostly sunny day - a few clouds appearing at times but passing quickly on the cold feeling light to moderate at times E'ly wind. Indeed, a cold day the maximum temperature at sunset was just 0.3C, I had to check it twice. Almost an 'ice day', rare on this essentially maritime island. Snow showers were frequent on the eastern side of England with snow in southern England. The evening was clear and frosty at first, but a gusty wind had picked up and the temperature had risen to 0.4C by 2200 GMT as cloud encroached from the East. [Pptn 0.0 mm; Max 2.1C; Min -3.2C; Grass -5.3C]
10th: The temperature continued to rise through the night and had reached 2.1C at 09 GMT, this value taking the maximum of the past 24-h and was, by convention, credited to the 9th. An overcast sky, grey and dull not the nice sunshine of the last few days so it was not a morning to linger over the obs. There was a force 4/5 ENE'ly wind too and visibility was good, but hazy . There was still enough snow cover on the ground and adjacent fields to record another day with snow lying, 2 cm in places that I measure - there was little change although the snow looked 'wetter' its structure was maintaining a similar depth. During the morning the cloud thinned and for a time the sky was brighter, but it was thicker totally grey again by noon. The mountains were mostly obscured. In the afternoon with the wind moderated there was light snow from 1350 GMT, but it did not settle. [Pptn 0.4 mm; Max 2.3C; Min -2.2C; Grass -4.9C]
11th: There was slow thawing of lying snow overnight, but there had been a little fresh snow deposited (about 0.3 cm) and it was snowing slightly at 09 GMT. There was snow lying on adjacent fields and garden although it was patchier. The temperature was 0.8C (dewpoint 0.0C) and the slight snow continued through most of the morning petering out about noon. The afternoon was a little brighter, especially over the Menai Strait, but there was no sunshine. There was no snow in Beaumaris, but was lying low on the mountain slopes of the mainland. At sunset a blood-red sun appeared under the cloudbase; after the sun had set he sky took on an unusual purplish-pink glow (right) may have been enhanced by dust particles in the air. Backward trajectory analysis (left), using the HYSPLIT model at the NOAA Air Resources Laboratory, indicated that parcels of air (1500 m, or more, AGL) over Anglesey at 16 GMT had been transported from north Africa between Egypt and the border with Libya. But, similar intense sky colours can be caused by polar stratospheric clouds, similar to that seen widely in Europe in February 2008 the result of very low stratospheric temperatures and high pressure (Hinz et al., Weather 64 (4) 2009). The temperature was falling again from 15 GMT and thawing snow had refrozen by dusk. At 18 GMT there was a frontal-wave low (983 mb) developing rapidly off Cape Finisterre tracking NE. [Pptn 0.2 mm; Max 2.0C; Min 0.4C; Grass 0.2C]
12th: The approaching low had deepened 971 mb at midnight. The air temperatures kept around freezing until 02 GMT, rose then fell again before rising to a 24-h maximum of 2.0C at 09 GMT. There was still some snow lying in places around Llansadwrn. Pressure 1008 mb was falling as low 965 mb was off the W of Ireland. Isobars were tightening on the chart and there was a moderate to strong SE'ly wind. Cloud was banked over the mountaintops and there were some lenticular altocumulus clouds hanging seemingly motionless, but continuously churning, in their lee. Dull at first the morning brightened and there was a little sunshine by 11 GMT; a band of moderate to heavy frontal precipitation was over SW Ireland and SW England. The afternoon had some weak sunshine, the temperature rose to 4.1C thawing some snow, before turning dull with strengthening wind for a time around 1600 GMT. There was less wind by evening and between 1830 and 2000 GMT ice crystals were blowing around in the air. They could be felt on the skin, but did not settle out or wet patches of dry concrete. Just before midnight there was a little snow. [Rain 0.2 mm; Max 4.1C; Min -0.1C; Grass -2.5C]
13th: Slight snow and still snowing at 09 GMT, but not settling very much on the ground here. It was a different matter in NW Anglesey were there was a covering in Gwalchmai and once more snow on the beach above the high tide mark in Rhosneiger. On the mainland there was drifting snow in Llanfairfechan making higher roads impassable and resulting shutting of the village schools, while in Bangor and Menai Bridge as in Llansadwrn, snow was not settling on the ground. Snow was heavy over parts of Wales with several mountains roads impassable due to deep drifts including Pen-y-pass, the Crimea Pass and the Horseshoe Pass in Denbighshire; 800 schools were closed. Slight snow was continuous here through the day with no accumulation here, but on the mountains it was settling. Although amounts were small windblown snow was deep in places. Thirty members of the Ogwen Mountain Rescue Team, with dogs, were called to Aber Falls when a head torch was found in water below a large avalanche of snow. Nothing was found after searching and probing for 3 hours. [Pptn 0.8 mm; Max 2.5C; Min 1.0C; Grass -0.2C]
14th: A bright morning with a light SE'ly breeze with lenticular altocumulus, a mackerel sky developed briefly around 09 GMT a hint of a change in the pattern of weather. There was snow in patches on the ground and low on the mountains mainly on the Carneddau and Ogwen Valley, to the W there was less remaining. Snow was thin on slopes where it had been blown off into drifts and gullies A ground frost overnight had refrozen the remaining snow and ice at the weather station, but it was soon thawing again and in sunshine by afternoon had mostly disappeared. During a survey of surrounding fields I saw a flock of curlew (40) feeding and then rising to do a circuit before returning. There were a few redwings, but not the numbers expected (we have seen few in recent years) and several lapwings and of course flocks of starlings that fly in soon after daybreak and fly off again before dusk. These have favourite fields so I know where to look, they go for the older pastures and they are not seen on newer leys or those used for cereals. They also seem to avoid those used for distribution of liquid wastes (seagulls are seen there), but do not mind traditional dung spreading. After sunset (unspectacular today as the dust had moved away) the sky cleared with a ground frost refreezing partially thawed grassy area. [Rain 2.9 mm; Max 8.4C; Min 0.7C; Grass -0.7C]
15th: By midnight cloud associated with a warm frontal system over Ireland was encroaching and the temperature began to rise. There was light rain from 04 GMT and the temperature had risen to 8.3C by 0830 GMT with a lull in the rainfall. At 09 GMT the temperature was 8.0C, visibility poor and there was a moderate shower of rain in a force 5/6 S'ly wind then light rain until about 1030 GMT. All the snow had disappeared here, but some grassy areas felt hard underfoot although the soil surface was soft and with a temperature of 1.7C at 5 cm depth. There were deep snow patches on the mountains as low as 350 ft with large areas remaining at higher levels. The day was overcast, but was a little less windy until evening when things livened up. By 2200 GMT the SE'ly was near gale to gale force 8 and there were very strong gusts with twigs being broken off the trees. [Rain 5.8 mm; Max 10.9C; Min 1.6C; Grass -1.4C]

The first 15 days had a mean temperature of 1.2C well below the average of the past decade (-4.5) and 30-y 1971-2000 [-3.7] monthly averages. The 10 air frosts were (+7.0) and 15 ground frosts (+2.4). Days with sleet/ snow were 10 (+8.3) and snow lying 9 (+9.0). Precipitation was 18.0 mm (16%) and [18%] of the monthly average.

16th: As an occluded frontal system moved across after midnight the temperature fell 3C and the S'ly wind reached force 7/8 with strong gusts continuing for about 3 hours. There was light rain from 0100 to 0700 GMT and the sky was still overcast at 09 GMT. Things were back to normal, a gale to note, a decent amount of rainfall to measure, the ground was no longer hard underfoot and the 8.2C felt really warm! And, I heard the bleating of new born lambs put out nearby. Soil temperatures were recovering with 5.6C seen at 5 cm depth. Lowest was 2.8C at 20 cm up from 0.4C on the 9th, at 50 cm up to 3.2C from a low of 2.7C yesterday, there was no change in the 4.9C at 100 cm. After a slight shower of rain a few breaks appeared in the cloud by 1030 GMT. We have seen no sign of wrens about the garden (good numbers in recent years) since the cold weather, they can be hit badly being so small, another small bird the goldcrest has been seen going in and out garden conifers. Robins are plentiful and so are the tits and blackbirds; thrushes are fewer, but have been seen. The sparrows have returned too, one a week ago has been joined by 4 others. The frontal cloud hung around all day and there was no bright sunshine. Towards dusk there was mist across the fields and some colour developed in the sky at sunset, but with cloud in the W the sun was not seen. Misty and overcast during the evening with little or no wind. [Rain trace; Max 8.9C; Min 7.0C; Grass 5.8C]
17th: After dawn cloud started to clear and the temperature on the grass fell to -0.4C. By 09 GMT cloud was increasing again with banded jetstream cirrus overhead the station, a bank of cumulus over the mountains and altostratus encroaching from the south-west. Visibility was poor to moderate with mist obscuring the mountains most of the day. The sky began to clear during the morning and, after another patch of cloud around noon cleared, the afternoon was mostly sunny though at times weak. A flush of snowdrops have appeared on grass between fallen leaves, small at the moment, but plenty of them. After dusk with clear skies there was a very good view of the new Moon and Venus low in the SW across the fields. Later sea mist rolled in. [Rain tr fg; Max 8.5C; Min 2.7C; Grass -0.4C]
18th: A misty night with sea fog increasing giving one of those rare mornings here that fog could be recorded at 09 GMT. Mist and fog persisted through the morning, the result of being conjunction of moist warm air to the W and colder air to the E. In the afternoon the sun was trying breaking through at times, more so to the E of here giving views of the Carneddau, but not of Snowdon to the W with fog persisting on the coast. During the evening the mist cleared at times revealing patchy cloud cover. [Rain 0.0; Max 8.0C; Min 4.0C; Grass 1.5C]
19th: By morning the sky was mostly clear with very good visibility especially at higher elevations there being a temperature inversion (6C in Llanberis). There was a little mist and smoke in the Strait to the E towards Conwy, but to the W it was clear with a good view of Lleyn. At 09 GMT there was a 6/8 covering of high and moderately high cirrostratus and altostratus cloud, with a bank of cumulus over the mountains. Temperatures had been falling reaching their minima and there was silver frost and glaze of ice on the grass. The day was bright with mostly weak sunshine, during the afternoon thicker cloud encroached. It was a good drying day with the SE'ly f3/4 2.2 mm was evaporated from the Piche evaporimeter housed in the Stevenson Screen. The evening was overcast so that temperatures kept above freezing. [Rain 6.0 mm; Max 7.8C; Min 2.4C; Grass -1.0C]
20th: There was no overnight ground frost, the -0.5C recorded was yesterday morning after 09 GMT (I record 24-h readings, but usually reset the thermometer at 21 GMT). There was rain from 0230 GMT and was moderate to heavy between 04 and 05 GMT. On the mountains the temperature at 2000 ft was low enough for wet snow to be falling. The day was dull with intermittent light rain and drizzle at times continuing into the evening when I had the suspicion precipitation was sleety between 20 and 22 GMT. [Rain 3.4 mm; Max 4.6C; Min 2.3C; Grass -0.5C]
21st: After midnight the precipitation had stopped and the sky cleared by dawn with the temperature on the grass falling to -1.7C. Atlantic-low 964 mb was W of Ireland tracking N and cloud ahead of a rain-bearing warm front encroached by 09 GMT. There was a little fresh snow on the mountains as low as 1500 ft centrally on the Carneddau and there seemed little change in the large snow patches. The morning kept dry, even bright at times, the light SSE'ly breeze strengthening force 3/4, with thickening cloud by afternoon, and force 6/7 by evening with light rain. [Rain 3.6 mm; Max 10.4C; Min 1.2C; Grass -1.7C]
22nd: The wind moderated and rain petered out around 03 GMT then with some cloud clearance by dawn shallow fog developed across the fields. Patchy fog lingered until after 09 GMT as the morning slowly brightened. Pressure 1014 mb was rising in a ridge as the low retreated north-westwards. By noon there was weak sunshine and with clearing skies over Anglesey there was a sunny end to the afternoon. Moderate to good visibility was restricted all day by mist so that the mountains could not be seen clearly even late in the afternoon. After an orange sunset shallow mist began to form again on the fields, but there was light from the half-moon by 18 GMT and under some clear sky -0.4C was recorded by the grass minimum thermometer, but fog developed by 22 GMT. [Rain 0.2 mm; Max 9.5C; Min 4.0C; Grass 2.3C]
23rd: Variable patchy fog with the sky just visible overhead and a light N'ly breeze. At 09 GMT the moderate fog and low cloud was thick enough to give some spots of rain. Fog continued variable with the sky sometimes visible then closing in again. The sun started to break through before 11 GMT, but sunshine was weak and by afternoon cloud had thickened again. There was a glimpse of brightness in the west as the sun set, after dusk the sky cleared and there was another ground frost. [Rain 0.2 mm; Max 7.0C; Min 3.0C; Grass -0.4C]
24th: From dawn the cloud was low and thick enough to give some fine drizzle. At 09 GMT it was calm and drizzle falling under a uniform grey sky with poor visibility, but soon petered out. The sky continued overcast during the morning with a bright spells early in the afternoon the sun weakly appearing (no bright sunshine) before disappearing again. Winds were light and variable before a NW'ly flow of air drifting chimney smoke set in late in the afternoon. There were shower of rain from 1800 GMT turning to slight sleet before 2200 GMT when the temperature fell below 3.5C. [Rain 1.9 mm; Max 5.5C; Min 2.0C; Grass -1.0C]
25th: Overnight precipitation had fallen as snow on the mountains above 1500 ft, there was not a lot at lower levels, the old patches showing through, but the tops looked well covered. Mostly cloudy with a cold feeling E'ly breeze, but there was a little sunshine for a while in the afternoon. Redwings were seen again on their favourite field near the village, but not as many as during cold spells in the past. I have seen a wren on 2 or 3 occasions, so they have survived the cold so far. There are catkins on alder and hazel. More winter heliotropes have come into flower and 1 or 2 crocus have appeared in the garden with more snowdrops opening. Good, but hazy visibility during the day becoming misty during the evening. [Rain 0.0 mm; Max 4.7C; Min 2.8C; Grass 0.4C]
26th: Dull and overcast with a uniformly grey blanket of cloud. There was no frost for the 2nd night and with a relative humidity of 83 % and a light E'ly breeze concrete and yellowish looking grass was dry. Soil was damp, but firmly muddy underfoot. Pressure 1042 mb had risen in a ridge over the UK developed from high 1045 mb over Denmark. Low 976 mb was over the N Norwegian Sea with associated fronts brushing over the N of Scotland. The day continued overcast, dull and sunless with smoke haze increasing through the day. There was a brief pink colour in western clouds as the sun set with haze taking up a slight purple hue. This phenomenon, seen widely in southern Britain with clearer skies, could be due to stratospheric clouds as mentioned on 11th. At 19 GMT the moon could be seen through breaking through thin cloud and haze. [Rain trace; Max 4.5C; Min 1.4C; Grass 0.7C]
27th: Cloud had thickened up by morning and there was slight drizzle. Pressure 1034 mb was falling with warm frontal cloud over the Irish Sea slowly moving south. The temperature at 09 GMT was 4.5C, highest of the past 24-h. The morning was dull with occasional drizzle this turning into a spell of light rain from noon until 15 GMT. The temperature rose to 7.8C by 1800 GMT then falling as a weak cold front, associated with development of a wave and low over the S Baltic, passed over. There was no precipitation and the sky kept overcast resulting in another sunless day. [Rain 2.4 mm; Max 7.8C; Min 1.5C; Grass -0.5C]
28th: Low 981 mb over the S Baltic brought more wintery weather into N Europe, with a strong showery northerly airflow developed over the North Sea. Here with pressure on 1019 mb the wind had backed NW'ly, but was light. The morning was mostly cloudy, again thick enough to produce some drizzle around 09 GMT. Breaks in the cloud were very few and far between, but by afternoon the cloud had thinned and there was weak sunshine. The cloudbase persisted around 2500 ft against the mountains, the tops remained obscured throughout. Large patches of snow remain on the northern slopes, particularly under Carnedd Llewelyn above 1000 ft, but there are a few small ones left as low as 600 ft. By the end of the afternoon cloud had thickened again and there was spell of light rain from 1800 GMT then moderate to heavy rain from 2230 GMT. [Rain 12.4 mm; Max 7.6C; Min 4.0C; Grass 0.5C]
29th: Pressure had fallen to 992 mb by 03 GMT with a frontal-wave low developing over the Irish Sea. Rain continued until just after 03 GMT and had turned showery by 08 GMT when there was a shower of rain and small ice pellets. These were 2 mm diameter, hard, translucent and mostly conical in shape. These ice cones may have been partially melted, snow pellets that had refrozen into hard cones of ice; the repeating process would eventually form larger hail. At 09 GMT pressure 996 mb was rising; there were in the vicinity being driven in from the Irish Sea on a moderate to fresh N'ly breeze. There was a heavier squally shower of rain and ice pellets at 0930 GMT the beginning of a series of showers, some prolonged and ending at 1020 GMT with large flaked snow. Snow settled on the mountains above about 1000 ft. By 1130 GMT the sky started to clear and it was sunny before noon. Showers persisted in places, a moderate shower of snow pellets and snow almost covered the deck of the Britannia Bridge and road to the Four Crosses at 1520 GMT. This missed Llansadwrn, but we had some more (snow pellets and snow) in the evening that left a covering on the ground and raised surfaces between 20 and 22 GMT. [Pptn 2.5 mm; Max 5.0C; Min 3.5C; Grass 3.0C]
30th: Slight showers of snow pellets and snow flurries continued to move across Anglesey after midnight leaving a sprinkling in many places by morning, that included above the high tide mark on Rhosneiger beach. Here a sprinkling on the ground with fresh snow pellets, but not enough overall to record snow lying at 09 GMT. Pressure 1002 mb was rising and a clearing sky led to a mostly sunny morning. Visibility was very good to good with light smoke haze. A line of showers (cloud street) in an unstable WNW'ly air flow (see MODIS Aqua satellite image left) persisted over the Irish Sea to the West through the day, stretching from the Isle of Man, past Anglesey and Lleyn, crossing Cardigan Bay to hit Pembrokeshire then Cornwall. In this case the clouds went on to Brittany as well. The line moved further East during the afternoon brushing Anglesey, when the photo (right) was taken. Such a narrow line of clouds can lead to heavy rain or snow over land and has become known as a Pembrokeshire Dangler (a name recently coined by Jon O'Rourke). It was sunny here until 1615 GMT when the sky turned cloudier and there were a few small flakes of snow. Snow pellets and snow showers during the evening from from 20 GMT left a light covering on the ground. [Pptn 2.6 mm; Max 4.6C; Min -0.2C; Grass -3.2C]
31st: Snow showers at 01 GMT and again just after 05 GMT left 1.5 cm of lying snow by morning. At 0815 GMT there was a shower of snow pellets, some were smooth and conical shaped while others (large hail) were encrusted with ice and measured 9 mm diameter. These peppered the surface of the snow leaving holes the hail sinking to the bottom. High 1021 mb was over the Atlantic, pressure here was 1005 mb and with low 987 mb over S Norway and the WNW'ly wind again persisted all day. There were snow showers off the Irish Sea during the morning (small flakes 1025z and large flakes 1100z) turning to wet snow as the temperature rose. By 13 GMT there was a little sunshine, but there were some more snow pellets and snow around 1520 GMT and 1800 GMT. [Pptn 6.4 mm; Max 4.2C; Min -1.7C; Grass -5.2C]

The month ended with a mean maximum of 5.2C, lowest since before 1980, (-2.9) and [-2.2] of average. The mean minimum was 0.7C, equal lowest since 1997 ranking 4, (-2.5) and [-1.7]. The mean was 3.0C, lowest since 1985 ranking 3, (-2.7) and [-1.9] . Total precipitation was 52.6C, lowest since 2001 rank 13 since before 1928, (52%) and [60%]. Sunshine duration at RAF Valley was 67.4h (111%) and [123%], highest since 2006 and 15th highest on the Anglesey record since before 1930. Sunniest 6.6h on 8th; 6 sunless days.

February 2010

1st: A cold and frosty morning with remnant partially thawed snow pellets and snow refrozen overnight and crunchy underfoot. Snowdrops had advanced since last photographed on 17th January, but there are later this year. In recent years some have been out at the end of December! The mountains looked white with wintry precipitation down to 400 ft. In the standard copper raingauge precipitation had frozen into a lump if ice in the funnel and had to be melted. The heater in the autographic gauge had done its job and the funnel was clear. So, after melting the precipitation was 6.8 mm. A bright morning with some moderately high altostratus advancing from the W the sun was partially obscured and sunshine weak. Similar in the afternoon, but a line (or street) of cumulus clouds stretched from Anglesey to the mountains. Cloud thickened and there was light rain from 21 GMT. [Rain 6.8 mm; Max 6.2C; Min -1.0C; Grass -4.5C]
2nd: Light rain eased by 03 GMT before more light to moderate rain from 05 GMT until 08 GMT. The sky was overcast with low uniformly grey stratus at 09 GMT. There were small puddles of water and fields looked very wet the local soils being still near or at the point of water saturation despite rainfall being below average. Visibility was poor and there was some more light rain during the morning with a heavy shower in Bangor at 0950 GMT. The day continued overcast and sunless with continuous light rain with bursts of moderate rain around 15 GMT petering out around 1715 GMT. Soon the sky began to clear and ice formed on cold surfaces. [Rain 3.0 mm; Max 7.4C; Min -0.3C; Grass -2.6C]
3rd: After midnight the sky had become cloud covered again. Overcast at dawn with fog in the Menai Strait as far as the bridges at 08 GMT. Visibility at 09 GMT was good and clear with the sky overcast with uniform moderately high altostratus. There was some icy deposits left on the ground but these were thawing slowly with the temperature 1.2C (dewpoint (0.4C). Light rain turned to sleet for a while from 1110 GMT with snow falling on the mountains at 1000 ft. Later precipitation turned back to rain and the fresh at lower levels on the mountains had disappeared well before the end of the afternoon. Another sunless day, some brightness seen in the W reached here after the sun had set. There was a misty view of the moon rising above the mountains late in the evening. [Rain 4.2 mm; Max 5.8C; Min 0.2C; Grass -2.1C]
4th: Cloud was thinning, after some slight showers of rain, and a few breaks appeared overhead at 09 GMT, but they did not last long. There was a light SE'ly breeze and visibility was very good with early mist at low levels cleared away. The day kept overcast here and along the North Wales coast, but there were lee breaks on the mainland and it was bright with a little sunshine in Llanfairfechan. [Rain 0.1 mm; Max 9.7C; Min 1.2C; Grass -0.3C]
5th: There were light rain showers around 04 GMT and the sky was brightening at 09 GMT with a force 3 S'ly breeze. Overnight the minimum air temperature was 4.8C, although highest of the month it was -3.2C of the average of past 10-years. Moderately high altostratus, with some cumulus to the S at first, slowly thinned during the morning with with sunny spells developing by noon. A clearing sky in the afternoon brought sunshine and with the temperature rising to 10.4C encouraged a mistle thrush to start singing in nearby tall trees. The sky was clear after dark, darkness is much later on now about 18 GMT here, and the temperature on the grass soon falling below freezing point. [Rain 0.0 mm; Max 10.4C; Min 4.8C; Grass 3. 8C]
6th: A bright morning with mostly thin cirrus clouds and weak hazy sunshine. Water deposits on grass on the fields had frozen white, but was thawing by 09 GMT with an air temperature of 3.7C. Visibility was good, but there was mist at low levels and in the Menai Strait, but the mountaintops were clearer in a temperature inversion. Pressure 1014 mb was rising as low 997 mb over Cornwall at midnight, tracked SE towards Brittany and filling 1002 mb . Large deep low 952 mb was slow-moving over the Atlantic making little progress against high-pressure UK to Scandinavia. Unusually heavy snow was affected eastern parts of the USA from West Virginia to southern New Jersey including Washington. Record snow depths were reported with 60 cm in Washington and 90 cm in Maryland. Snow brought down trees, caused major power cuts and disrupted transport. Here weak sunshine during the morning gave way to pleasant hazy sunshine in the afternoon. Visibility was good with haze increasing as a few cumulus clouds developed over the mountaintops. The evening and night were clear, concrete had become damp and visibility was misty before midnight. [Rain tr fr; Max 8.2C; Min 2.1C; Grass -1.2C]
7th: Mostly clear with a little mist until just before dawn when thick fog (visibility <100 m) developed over heavily frosted fields. Slowly clearing to moderate fog (visibility 500m) by 09 GMT with the sun beginning to break through the overnight air minimum temperature of -1.5C rising to 0.2C. Pressure was 1024 mb and there was a light SE'ly breeze. At Valley snow grains were reported every hour from 03 to 08 GMT and light rain at 09 GMT. There was heavy frost on the grass here (minimum -4.5C) and slight ice glazing of concrete surfaces. The fog and clouds mostly clearing by 11 GMT to give a sunny morning and afternoon. There were a few clouds at sunset and the evening mostly clear at first with a ground frost and slight mist developing. [Pptn 0.1 mm; Max 7.5C; Min -1.5C; Grass -4.5C]
8th: Overcast with recent slight precipitation, possibly wintry. Stratocumulus clouds, associated with sheets to the N, were thinning overhead. Pressure was steady on 1017 mb in a ridge extended from high 1030 over the Norwegian Sea. There was a light to moderate E'ly breeze and visibility was only moderate in smoke haze. Soon the cloud was broken with some sunny spells and the temperature rose to 4.0C, but at Valley 7.2C was recorded. Cloudier later in the afternoon into the evening. At 2230 GMT there was a shower of snow pellets and snow as the temperature dipped to the 24-h minimum of 1.8C. [Pptn 0.2 mm; Max 4.0C; Min 0.1C; Grass -1.7C]
9th: No overnight frost and concrete and grass were dry. Cloud was breaking and the morning bright with weak sunshine then sunny spells. Pressure was 1017 mb in the ridge now drifting W, from high 1025 mb just off NW Scotland. The temperature was 2.9C (dewpoint -0.7C), there was a light to moderate NE'ly breeze and visibility was very good. At Beaumaris a line of cumulus clouds could be seen over the Snowdoina Mountains that had a little fresh snow around the summits. There was a moderate to fresh NE'ly breeze along the Strait stretching out the flag on the Lifeboat Station. There were scattered clouds around during the day with some sunny spells particularly in the afternoon with the sky almost clearing by sunset. There was a prolonged peach coloured twilight and a clear evening, in the absence of moonlight good for star watchers with a fine view of Mars quite high to the SE at 2200 GMT. {Valley 6.4C, 4.2h} [Pptn 0.0 mm; Max 4.6C; Min 1.8C; Grass 0.8C]
10th: Mostly clear sky at night with a light breeze, but cloudier by dawn. A ground frost with light white frost on the grass with a minimum of -1.0C. Pressure 1020 mb was rising with high 1027 mb over Rockall. Bright and soon sunny with cloud clearing again and very good visibility. Mostly sunny in the afternoon with a line of cumulus clouds over Snowdonia and another line to the N of here. Snow on the tops lay mostly on the Carneddau, with deep snow beds on northern slopes and gullies. Western mountains had less snow although Snowdon had a good covering around the summit. Another peach coloured twilight after the sun had set. [Pptn 0.0 mm; Max 4.6C; Min 1.1C; Grass -1.0C]
11th: Clear sky overnight, air frost was slow to set in until the light NE'ly breeze fell away by 0230 GMT and the temperature fell to -1.0C around dawn. There was slight white frozen dew on grass (min -3.8C, 0.1 mm measured by drosometer). A fine sunny morning with very good visibility, there was slight haze when looking into the sun. The temperature had risen to 0.5C (dewpoint -3.1C) at 09 GMT; pressure 1026 mb. Heavy overnight snowfall with some drifting (10 cm reported in Margate and 14 cm in Ramsgate) made driving difficult from Kent (200 schools closed) to E Sussex (60 schools closed). More snow fell during the day with low drifting snow reported at Manston during the afternoon on a strong N'ly wind. A mostly sunny day here, a patch of thin cloud moved across the sun just before 14 GMT, but cleared again. Cumulus clouds appeared over the sea to the NE at 16 GMT and scattered clouds moved across here by 1630 GMT with a slight shower of rain later. During the evening under clear sky moisture on the grass froze with the temperature falling to -2.8C by 2100 GMT. The air temperature fell to 0C before rising again as the sky turned cloudier. [Pptn trace; Max 4.6C; Min -1.0C; Grass -3.8C]
12th: Mostly cloudy overnight, but beginning to clear after dawn. Pressure was 1027 mb, visibility moderate and once again there was the light NE'ly breeze. A fine and mostly sunny day, with a few clouds at times over Anglesey. The mountains were cloudier, hiding a sprinkling of fresh snow above 2000 ft, starting the day with low cloud in the Menai Strait that was slow to lift during the morning and had not cleared the tops by late afternoon. There was a slight shower of rain before 2150 GMT. {Helens Bay 10.1C, Valley 8.0C & 8.0h, Tiree 8.3h} [Pptn trace; Max 5.7C; Min 0.0C; Grass -2.8C]
13th: Mostly cloudy at first, clouds becoming scattered with some sunny spells during the day before turning cloudier again towards dusk. Visibility was mostly very good and the wind, NE'ly force 2 at first, lessened through the day. There were some spots of rain during the evening. [Rain trace; Max 5.5C; Min 0.6C; Grass -2.3C]
14th: Again mostly cloudy with the mountaintops obscured under thin cloud that allowed glimpses of weak sunshine at first. Soon the cloud thickened and there was light rain on a warm front from just before noon not easing until after 1830 GMT. There were a showery bursts of rain around 2100 GMT and between 2300 and midnight containing a few small ice pellets. Total precipitation of 8.4 mm, was the largest of the month. {Mumbles Hd 9.2C, Manston 5.5h} [Rain 8.4 mm; Max 4.8C; Min 0.2C; Grass -3.5C]
15th: Overcast with no further precipitation until dawn when there was heavy drizzle then fog increasing until 09 GMT. Pressure 1006 mb was falling with deepening low 990 mb N Scotland and we were in warm sector air with a light SW'ly breeze. The fog soon cleared, but the morning kept overcast, occasionally brighter but no sunshine. There was showery rain from 1100, with heavier bursts around noon, through to 1900 GMT turning sleety when the air temperature fell below 3.5C during the evening. [Pptn 6.4 mm; Max 6.4C; Min 2.1C; Grass 1.9C]

The first 15 days had 31.2 mm of mixed precipitation (34%) and [41%] of the February average. The mean temperature was 3.5C (-2.1) and [-1.8] of the average for the month. Soil at 30 cm averaged 3.5C (-2.2).

16th: Precipitation during the night at 02 GMT and between 0430 and 0500 GMT was of snow. There was a thin layer of snow crystals on the roof of the Stevenson screen at 09 GMT and a little on the grass. Pressure was 990 mb with low 987 mb lying close to the NW off Malin Head. The sky at first was clearing, but with cumulus clouds in the vicinity there were wintry showers of sleet, small snow pellets and slight snow from 1000 GMT. There was fresh snow on the mountains at 2000 ft at 09 GMT and with further snow during the morning was as low as 600 ft by afternoon particularly on eastern Carneddau Mountains. The afternoon was brighter with a few sunny spells and the sky had cleared by evening with frost on the grass. [Pptn 2.0 mm; Max 6.6C; Min 0.1C; Grass -2.2C]
17th: Almost clear skies overnight with a moderately heavy white frost on the grass by morning. The grass thermometer had fallen to -6.0C, and air temperature in the screen to -1.7C with 11.8h frost duration. At 09 GMT the temperature was -0.5C (dewpoint -2.3C) under an almost clear blue sky, there was just a little cloud low in the sky to the SW. A sunny day, with a little cloud spilling over the tops of the Carneddau during the afternoon, but Snowdon remained in the clear with its white summits showing up well in sunshine. A little altocumulus in the W at sunset otherwise clear sky with frost on the grass well before the sun had set. Clear evening with new moon low in the sky to the NW. [Trace frost; Max C; Min -1.7C; Grass -6.0C]
18th: At 07 GMT there was heavy white frost on the grass, but this had melted before 09 GMT as moderately high cloud encroached. At 09 GMT there were a few small breaks in the cloud overhead and the temperature was 1.7C (dewpoint 1.2C), visibility was poor in mist. The morning slowly brightened as the cloud thinned and there was a little weak sunshine around noon. The afternoon was dull with thickening cloud and there was a mixture of snow grains, sleet and wet snow during the evening from 1800 GMT. The precipitation covered the ground, but had mostly disappeared by 2200 GMT. [Pptn 2.7 mm; Max 4.3C; Min -0.5C; Grass -3.5C]
19th: Clear spells with frost the air temperature fell to -2.2C, lowest of the month, and on the grass to -5.4C. Showers of snow grains and light snow before 09 GMT left a covering 1 cm deep. Light snow continued with a prolonged shower with very large flakes from 0950 GMT increased the depth to 2 cm by 1130 GMT. Snow was moderately deep at 2500 ft on the mountains with light snow lying at low levels on Anglesey including on sand above the high tide mark on Rhosneiger Beach. Snow flurries and showers of snow pellets continuing into the afternoon with a cumulonimbus cloud seen over the mountains, but there were some sunny spells when the temperature rose to 3.8C, lowest maximum of the month. After dark temperatures fell rapidly with frost forming on the grass where the temperature fell to -6.0C, lowest of the month. [Pptn 4.6 mm; Max 3.8C; Min -2.2C; Grass -5.4C]
20th: Snow fell between 04 and 05 GMT leaving up to 2 cm lying snow in the morning. The sky was clearing so that the snow on branches of trees glistened in early sunshine. At 09 GMT the temperature had crept up to 0.2C, but the snow was still dry and powdery. The snow had started to thaw before 1000 GMT when another prolonged snow shower with moderately large fakes came along. With low 982 mb near Denmark pressure here 996 mb was rising, there was a light SW'ly breeze and good visibility when it was not snowing. Some bright spells with a little sunshine in the afternoon when most of the snow disappeared locally. With the sky almost clearing by dusk there was another frost. [Pptn 3.0 mm; Max 6.9C; Min -1.3C; Grass -6.0C]
21st: With a frontal low developing over the Irish Sea after midnight there was unidentified precipitation from 03 to 04 GMT and large flaked snow from 0545 to 0730 GMT again enveloping tree branches and conifers. There was 2 cm of lying thawing snow at 09 GMT when the air temperature was 0.5C. The sky was clearing a little, but another band of cloud moved across by 1000 GMT bringing a slight fall of snow grains about 1 mm diameter. The day was mostly cloudy with no more precipitation. The sky was mostly clear by evening with a hard frost developing. [Pptn 0.1 mm; Max 4.3C; Min -0.7C; Grass -4.3C]
22nd: A bright morning with frost on the ground and a little remnant snow hiding away in a few shaded area of the garden. Pressure was 987 mb with a low 977 mb near the Cherbourg Peninsular and fronts strung out along Channel coasts resulting in a wet/ wintry day in the South. Here the day was mostly sunny with high thin cirrus clouds disappearing over Anglesey. There was a cold feeling light to moderate E'ly wind the temperature rose to just 4.2C during the afternoon. Visibility was hazy but good, the smoke haze thickening by afternoon. Cloud spilling over the tops of the mountains persisted well into the afternoon. A clear frosty evening under a little cirrus and a half Moon shining brightly. [Pptn 0.0 mm; Max 4.2C; Min -1.6C; Grass -4.8C]
23rd: Relative humidity was under 75% through the night, mostly cloudy at dawn and there was white minimal frost on the grass. The ground surface was frozen hard with the temperature at 5 cm depth down to 0.4C. Temperature at 30 cm was 2.5C and 100 cm 5.0C. At 09 GMT (0.4C, dewpoint -3.3C), with vigorous Atlantic-low 967 mb W Biscay, pressure here 991 mb was rising and the patch of cloud was thinning. The morning was bright; visibility was good although with moderate smoke haze. A band of precipitation on an occluded front associated with the low was near S Ireland and SW England tracking NE. Cloud thickened during the afternoon; there was a light fall of the easily missed snow grains at 1515 GMT (temperature 1.7C). After a few small flakes of snow at 1710 GMT there was a light fall of star-like ice crystals at 1830 GMT (temperature 1.6C). During the evening precipitation was wet snow covering the ground with a thin layer of slush this still persisting at 2200 GMT. The lowest evening air temperature of 0.5C was around 21 GMT thereafter rising slowly to 1.5C at midnight when precipitation was of sleet. [Pptn 3.7 mm; Max 6.4C; Min -1.3C; Grass -4.4C]
24th: Sleet continued after midnight before turning to intermittent rain, as the temperature began to rise more quickly after 01 GMT, the rain petering out by 0430 GMT. The temperature at 06 GMT was 6.4C, highest of the past 24-h, and was to fall a little to 6.1C (dewpoint 4.7C) at 09 GMT with a clearing sky. There was a light SE'ly breeze and 2 oktas cover of mostly cumulus clouds over the mountains with some lenticular altocumulus. The day was fine and sunny and the temperature 12.8C in the afternoon, in a SSE'ly Föhn-like breeze off the mountains, was highest of the month. A search of the wood revealed some bluebell leaves emerging beneath the shelter of ivy leaves, a few were 5 - 10 cm tall. Thrushes were singing a little, encouraged by the fine day they may well soon start nesting. Nesting boxes were inspected, 5 out of 14 were used successfully last season, the flat top of another was used by a blackbird; tits have been in and out of them most of the winter especially on fine days. The evening was fine with scattered clouds. {Gravesend 12.1C, Pembrey Sands 11.8C} [Rain trace; Max 12.8C; Min 0.4C; Grass 0.0C]
25th: A mostly cloudy morning with a little rain at 09 GMT and precipitation in sight over the mountains with crepuscular rays moving across the Nant Ffrancon Pass. Complex low pressure over the UK, here 987 mb centred over the Irish Sea. A band of rain was crossing S England, there was a showery trough over Wales with fronts over Scotland. Visibility was moderate to good and broken snow could be seen on lower slopes below 2500 ft with some as low as 1200 ft in Cwm Idwal. Large patches remain at lower levels some smaller ones as low as 500 ft mainly on eastern slopes of the Carneddau. A severe snowfall event affected Scotland with 50 - 80 cm snow reported in the Highlands with the Cairngorm ski slopes closed. The weight of snow had brought down power lines with many homes without electricity overnight, many schools were closed and the A9 made impassable with many spending the night trapped in their vehicles. It was still snowing. Another fine day here, not as sunny or warm the temperature reaching 9.1C. The evening was mostly cloudy, but fine. [Rain trace; Max 9.1C; Min 3.0C; Grass 0.8C]
26th: Overcast and another night without frost. The cloud was moderately high with the sun looming through at 09 GMT. Pressure 987 mb was rising with low 979 mb off Skegness just over the North Sea. The day was mostly overcast, a little brightness in the morning with gathering dark clouds in the afternoon as showers moved slowly across the sky. There was rain in Caernarfon at 1500 GMT, heavy rain with ice pellets around the bridges and Four Crosses at 1515 GMT. Here we caught the edge of the precipitation at 1520 GMT. Precipitation fell as snow on the mountaintops. The sky cleared during the evening with a ground frost developing under a nearly full Moon. [Rain 0.9 mm; Max 6.2C; Min 2.8C; Grass 0.9C]
27th: Cloud encroached after midnight and the sky was overcast at dawn with moderately high cloud so that the mountaintops were in the clear. Visibility was very good and clear of haze; some cumulus began to form around the summits over the snow fields around 09 GMT. Atlantic-low 977 mb was developing W of the Gibraltar Strait tracking off Iberia heading N; pressure 992 mb was falling within a complex low-pressure system over the UK. By 1030 GMT cloud was broken with some sunshine, but the afternoon was cloudier at times becoming overcast by evening. [Pptn trace; Max 9.8C; Min 1.6C; Grass -1.2C]
28th: At midnight rapidly deepening low 972, named Xynthia, was over Biscay approaching the coast of western France. Winds up to 90 mph, heavy rain and tidal surge produced flooding in the Vendee and Charente Maritime. The sea wall in Aiguillon-sur-Mer was breached and many people were drowned in their single storey houses as water level rose rapidly to rooftop height. Helicopters and boats were used to rescue survivors. Trees were brought down resulting in more deaths and over a million homes were without electricity. Over 50 people lost their lives through Portugal, Spain and France in the devastating storm. Here, it was overcast with recent unidentified precipitation and no frost overnight. Pressure here was 990 mb with Xynthia 971 mb over Normandy in France. Dull at first with the cloud thinning giving some brightness by 10 GMT. A few sunny spells came along during the day before a cloudier end to the afternoon. After sunset the cloud cleared revealing the full Moon and there was soon frost on the ground. [Trace frost; Max 6.5C; Min 2.9C; Grass 1.9C]

The month ended with a mean temperature of 3.5C, lowest since 1991 ranking 4 since before 1979, (-2.2) and [-1.8] of average. The were 10 days with sleet or snow, equal highest 1996 ranking 2 since before 1979, and 3 days with snow lying at 09 GMT, most since 2006. Precipitation totalled 46.2 mm, largest since 2008 but ranking 23 lowest since before 1928, (51%) and [62%] of average. It was the sunniest February since 2008, one of the 17 sunniest on the Anglesey record, with sunshine duration at Valley 92.1h (111%) and [122%]. Sunniest day was on the 17th with 8.9h, there were 3 sunless days.

March 2010

1st: DYDD DEWI SANT: For the first time in many years there were no daffodils in flower to photographs on St. David's Day. In recent years with warming temperatures daffodils have become a familiar sight in gardens at this time, but this years just one or two tightly closed buds. There is a fine display of snowdrops and crocuses. It was a fine morning with hazy sunshine although temperatures continued about 2C below average. Pressure was 1010 mb with the low Xynthia 980 mb over the S Baltic Sea and Germany. A mostly sunny day, turning cloudier for a while around noon, but a sunny afternoon with improving visibility as the temperature rose to 11.3C. A clear frosty evening. [Trace frost; Max 11.3C; Min -0.6C; Grass -4.2C]
2nd: Another fine morning with the white frost on the grass beginning to melt. A ridge of high-pressure was developing over the UK with rising pressure here 1022 mb; the low had filled to 987 mb and was over St. Petersburg. Another low 982 mb was off Iberia while pressure was high 1025 mb over Tunisia. The mountaintops looked very white with a good cover of snow and frequent snow patches as low as 400 ft near Abergwyngregin. The afternoon was bright as high cloud encroached with weak sunshine continuing through to sunset. The evening and night were mostly cloudy. [Rain 0.0 mm; Max 8.7C; Min -0.5C; Grass -4.4C]
3rd: Overcast with moderately high altostratus clouds that were beginning to thin giving a little weak sunshine at times. The temperature at 09 GMT was 3.9C (dewpoint -2.7C with a relative humidity of 62%), visibility was very good and clear. The day kept overcast with weak cloud obscured sunshine through the afternoon as the relative humidity fell to a low 39%. Brighter in the W at sunset, no colours seen, and a clearing sky during the evening with dew freezing on the grass. [Rain 0.0 mm; Max 8.8C; Min 1.7C; Grass -0.7C]
4th: A bright morning with a large covering of mixed cirrostratus and cirrus clouds. At 09 GMT a partial 22° solar halo and parhelia (mock suns, or sun dogs), showing bright colours, together with a white colourless wide, almost horizontal, portion of the parhelic circle (mock sun ring ) were observed for over an hour as the sun rose above the Carneddau Mountains. The parhelic circle was very bright outside the 22° halo, fainter within . The sky was clearing overhead before noon with patchy cloud remaining over Snowdonia. The afternoon was clear and sunny with the relative humidity falling to 50%. A prolonged twilight was an azure blue sky over a pale peach colour above the horizon in the West. [Trace frost; Max 8.9C; Min -0.1C; Grass -3.0C]
5th: Becoming cloudier since dawn, but there was still frost on the grass. The grass thermometer had been down to -4.6C and measured dew deposition was 0.3 mm. There was condensation on the inside of the octapent raingauge funnel, but nothing collected in the bottle. Pressure was 1032 mb and there was a light SE'ly breeze. The day was sunny at times (maximum 9.8C), but there were some dark cumulus clouds around casting a lot of shade when they passed over in the afternoon. The evening was cloudier becoming overcast. {Milford Haven 9.8C} [Rain tr; Max 9.8C; Min -0.8C; Grass -4.6C]
6th: A mostly cloudy morning, and with no overnight frost. There had been a few spots of rain, so a trace was noted. The temperature at 09 GMT was 5.6C (dewpoint 3.5C) and pressure 1029 mb. I noticed 2 hares frolicking in the adjacent field and jumping over the stone wall into the wood where I sometimes see them. The cloud slowly broke, lifted and thinned through the morning so that by afternoon it was mostly sunny. A little cloud remained over the tops of the snowy mountain summits. Cloudier again by sunset when a pink and and purple glow was seen in the West. By 1900 GMT the sky was clear with bright stars visible and a hard frost forming on the grass. [Rain 0.0 mm; Max 8.8C; Min 2.4C; Grass 1.5C]
7th: A clear sky with a peach twilight at dawn the sun rising at 0715 GMT. Hardly any cloud at 09 GMT; the air temperature was -0.7C (dewpoint -5.7) and visibility good or very good with haze in the Strait with mountaintops in the clear. The overnight minimum was -2.5C, lowest of the month. A white frost on the fields was just starting to melt (0.2 mm measured by drosometer). A sunny morning, little or no wind; mistle thrushes were singing adding to the song of robins and other birds that is growing in intensity these sunny morning, but cold morning. An almost cloudless sunny day although the temperature rose to just 5.3C lowest of the month. The sky with a little cloud in the W briefly turned pink and purple after the sun had set. A clear night frosty night. {Trawsgoed 7.0C, Valley 10.8h} [Rain 0.0 mm; Max 5.3C; Min -2.5 C; Grass -6.8C]
8th: Another hard frost with -7.0C recorded on the grass and 0.17 mm frozen dew measured by the drosometer. There has been a lack of hoar frost during this cold spell. As yesterday the overnight minimum temperature was -2.5C, lowest of the month. The sun rose now much further E along the mountain range rose at 0703 GMT. A cloudless morning, good visibility just a little hazy. Pressure was steady on 1033 mb within the high over the UK. Another sunny day the relative humidity falling to 40% as the temperature rose to 7.2C. With a cloudless sky there was the maximum possible sunshine. Another pink and purple colour to the thick haze after sunset then a clear frosty night. {Aberporth 10.9h} [Rain 0.0 mm; Max 7.2C; Min -2.5C; Grass -7.0C]
9th: Another morning with white frost on the grass that began to melt around 09 GMT. Mostly frozen dew with slight hoar frost. Mist early then haze moderately thick in the Menai Strait up to about 2000 ft with the mountaintops in the clear, indicative of a temperature inversion. Pressure was unchanged with the high 1034 mb centred over Scotland. A little moderately high cloud to the SE then a few cumulus clouds developed during the morning. In the afternoon a cloud street formed across Anglesey and the Snowdonia Mountains. A large bumblebee was seen for the first time this year, foraging around the crocus that are in full bloom. No honeybees have been seen, and it is unlikely that any will be seen as the apiary sited within 0.5 km of the weather station has had to be moved away. Honeybees in the garden have been a feature for many years, and frequently commented upon in these pages, and will be sadly missed. The cloud disappeared before the end of the afternoon leaving a very hazy sky the now more familiar pink and purple colour was prolonged, but more subdued, lasting well after sunset. A clear evening before cloud encroached later. {Hawarden 10.2C, Aberporth 10.8h} [Rain 0.0 mm; Max 9.1C; Min -0.6C; Grass 4.6C]
10th: Scattered clouds and some early mist were burning off to give a sunny, but very hazy morning. Pressure steady on 1033 mb would begin to decline through the day. A fine and mostly sunny day, the haze thinned and cleared by afternoon so that clear views of the mountains could be seen. Two large bumblebees were seen on the heathers in full flower, a solitary pied wagtail that has been in the garden all winter has moved off. We frequently have a wagtail overwinter, and although the habitat is suitable here they are do not nest here unless it returns with a mate this year. Most birds are pairing up, 2 pairs of robins were displaying quietly until a fifth turned up when there was trouble! Tits continue to inspecting the nest boxes and I suspect thrushes and blackbirds are already nesting. There is still a lot of snow on the mountaintops, unbroken in places, with large snow beds persisting around 1000 ft. Smaller patches are still surviving at 400 ft, perhaps lower in places including Aber Valley around the headland at Penmaenbach on shady NE-facing crags. Clearer sky in the W at sundown with a brief vivid red and purple glow in the sky at 1805 GMT. A clear evening with frost and mist soon developing in low lying areas. {Milford Haven 9.8C, Valley 10.2h} [Tr melting frost; Max 9.1C; Min 0.8C; Grass -3.2C]
11th: Mostly cloudy at first, but the sky was clearing before 09 GMT melting the extensive white frost on grass. The soil surface and concrete was dry. Pressure 1028 mb was falling very slowly as occluded frontal cloud associated with a Polar low to the N of Scotland moved South. Initial cirrus and cumulus clouds cleared to give a mostly sunny morning. Small species daffodils are now beginning to flower in the garden together with the first dandelion and daisy on the lawn. Cirrus clouds remained over the snowclad mountains in the afternoon with moderately high cloud encroaching before sunset. There was a little clearance during the evening enough for a touch of ground frost before thicker cloud encroached from the North.. {Milford haven 9.8C, Valley 10.6h} [Rain 0.2 mm; Max 7.6C; Min -0.8C; Grass -4.8C]
12th: The occluded front was over Anglesey at midnight and there was a shower of rain with a few small ice pellets about 0445 GMT. Pressure was 1024 mb and the sky had started to clear before 09 GMT. The N'ly breeze was freshening force 3/4 and visibility was moderate the haze obscuring a clear view of the mountains. The best of the day's weather was in the NW as during the morning the sky cleared over Anglesey, although a persistent bank of cloud over Snowdonia lifted only slowly through the day. Later a few cumulus clouds developed over Anglesey cloud cover increasing during the evening. {St. Athan 11.5C, Valley 9.3h} [Rain 0.0 mm; Max 8.3C; Min 3.2C; Grass -0.7C]
13th: An overcast and dull morning with cloud covering the mountaintops . Pressure 1033 mb was rising as the Atlantic-high 1038 mb to the W of Ireland intensified. Visibility was good and there was a light NW breeze and the morning kept overcast with a few bright spells and occasional weak sunshine. The afternoon had cloud thick enough to produce spells of fine rain. The sky cleared after dark with ground frost developing. [Rain trace; Max 8.6C; Min 2.3C; Grass -1.4C]
14th: The morning was damp morning with much condensation on the copper rain gauges. After a mostly clear night the sky was becoming cloudier at 09 |GMT when the temperature was 5.5C (dewpoint 5.3C, RH 98%). Pressure was steady on 1032 mb with Atlantic-high 1037 mb off SW Ireland. With scattered clouds the morning became sunnier and with few in the afternoon pleasantly warm with the temperature 12.3C, a rise of 11.3C. I missed the honeybees, they would have been humming on the banks of heathers on the rockeries, but there were 3 large bumblebees. The absence of honeybees will make a difference to setting of fruit bushes and trees in the garden. A little cloudier at the end of the afternoon, but clearing later in the evening, ands yes there was another ground frost. {Pershore 14.1C, Valley 11.6C and 8.5h} [Rain 0.0 mm; Max 12.3C; Min 1.0C; Grass -2.5C]
15th: Cloudier from dawn with a little brightness and weak sunshine at first. Pressure 1029 mb was beginning to decline and with the jetstream persistent over Iberia and the Gibraltar Strait and the Med beginning to fragment and likely to move N, the settled spell of weather is perhaps slowly coming to an end. The morning was soon dull, the afternoon overcast with slight showers of rain between 1330 and 1430 GMT. There were some breaks in the cloud by 2000 GMT. [Rain trace; Max 11.0C; Min 2.4C; Grass -1.6C]

The first 15 days have been remarkably dry with just 0.2 mm measured rainfall. The mean temperature 4.6C was well below normal (-2.4) and [-2.1] of average and there was ground frost every night. Sunny with 109 h reported at Valley already (83%) and [103%] of the average for March .

16th: A bright morning with a deep red sun starting to rise about 0640 GMT now well E of the Carneddau Mountains. Moderately high altostratus cloud at first with cirrostratus moving across by 09 GMT. There was a partial 22° solar halo, but no 'dogs'. Soon sunnier with a light to moderate S'ly breeze and very good visibility. The glory-of-the snow have appeared in the garden, photographed 2 days earlier than last year, the cold weather had not delayed their flowering. There was still plenty of snow on the tops of the Carneddau, but patches at low levels were fast disappearing. Mostly sunny, but becoming windier in the afternoon and cloudier by 1700 GMT. There was rain on a frontal system falling on western Ireland by 1800 GMT, but was not to reach here before midnight. [Rain 1.2 mm; Max 10.8C; Min 2.3C; Grass -0.7C]

On this day in 1979 we were hit by a 48-h blizzard that continued on through the 17th. There was 15 cm of level snow and 2 m drifts in the garden and 2-3 m drifts blocking the Llansadwrn to Beaumaris road.

Duncan Brown alerted me to reports of dustfall in central Anglesey (and N England). While there has been local dust around during the dry weather there have been duststorms in northern Africa with Saharan dust transported to S Europe in recent days. Backward trajectory analysis using HYSPLIT, courtesy of NOAA ARL Website, revealed that air arriving between 500 and 1000 m AGL at 1400 GMT today over central Anglesey could have picked up dust N of large storms in S Algeria, Mali and Mauritania on the 16th that could have been washed out in this afternoon's rain. .

Precipitation, most falling in the second half of the month, totaled 84.5 mm, highest since 2008 ranked 27 since 1928, (133%) and [100%] of the averages. There were 17 (+2.7) dry (<0.2 mm) days. The mean temperature 6.4C, lowest since 2006 ranked 11 since before 1979, was (-0.7) and [-0.4] of the averages. The 147.0 h sunshine duration at Valley was sunniest since 2007, rank 10 on the Anglesey record since before 1930, and (112%) and [139%] of average. Sunniest day was on the 7th with 10.8h; there were 4 sunless days.

April

1st: With mostly clear sky around dawn there was a ground frost (-2.7C) the air temperature keeping above freezing at 0.4C was lowest of the month. The sun rose at 06 GMT as an orange ball, now well to the East of the Carneddau in the direction of Conwy. Earlier there had been some snow pellets and a little sleet. By 09 GMT the sky was mostly cloudy with the snow covered mountaintops obscured, but fresh wet snow was seen as low as 400 ft. Pressure 1006 mb was rising as a ridge of high-pressure crossed from the West. The low of yesterday was filling, 986 mb off the NE off Scotland, but another Atlantic-low 993 mb W of Ireland was deepening and heading our way. There was a slow-moving detached warm front mid to S Wales, but here it was a fine day with increasing amounts of sunshine by afternoon and a sunny early evening. [Rain 0.1 mm; Max 10.5C; Min 0.4C; Grass -2.7C]
2nd: A fine and bright morning, but there were cumulus clouds in the vicinity threatening showers. Pressure was 996 mb with low 988 mb SW Ireland. There was a light shower at 1045 GMT then some more sunshine. Well, it's April after all. During the afternoon the showers pepped up a bit and there was a shower of small hail in Benllech at 1705 GMT, but we had just rain here. By evening showers had left a covering of fresh snow on the Snowdonia Mountains above 2500 ft. Showers continued up to 2300 GMT. [Rain 3.9 mm; Max 9.5C; Min 1.5C; Grass -2.0C]
3rd: Another bright morning, again cumulus clouds were seen and we did have a few spots of rain during the morning. Low 992 mb was over Cornwall, but here pressure 998 mb was rising and the day kept mostly dry with sunny spells coming along in the afternoon. There was light fresh snow on the mountains at 2000 ft, mostly centrally between Carnedd Llewelyn and C. Dafydd with a good covering along the ridge to Penyrole-wen. Today, I got the mower out!. Usually in recent years it has been kept busy during the winter as the grass continued to grow. Not this year. Checked out the mower, but there was little to cut, the grass still not growing very much. The leaves of bluebell are quite tall, but still no flowers. We have seen a peacock butterfly that managed to overwinter; there are plenty of ladybirds about too seemingly unaffected by the winter weather. Broken cloud cover during the evening and night. {Gravesend 12.6C, Isle of Portland 29.6 mm, Valley 8.4h} [Rain trace; Max 12.2C; Min 2.5C; Grass -0.8C]
4th: Bright, fine and mostly sunny with pressure 1012 mb rising, a light W'ly breeze with good though hazy visibility. There were once again cumulus clouds in the vicinity, but these diminished through the day and there were clear views of the snow covered mountaintops later in the afternoon. Hawthorn leaves are opening in the wood, but not yet on roadside hedges, and there is a fine display of snakes head fritillaries coming on the 'meadow area' in the garden. We started with just 4 plants, but within a few years they have seeded themselves and we now have too many to count and they are spreading into the lawn. Lesser celandine, however, is spreading and becoming a problem. By evening frontal cloud was encroaching from the W and the wind was freshening. [Kinlochewe 12.7C, Milford Haven 10.0C, Capel Curig 13.8 mm] [Rain 11.1 mm; Max 11.8C; Min 1.8C; Grass -0.9C]
5th: Overcast with spots of rain on the freshening S'ly breeze. Slight rain during the morning and becoming brighter with some sunny spells in the afternoon. Low 972 mb was W of Rockall, S of Iceland, and the wind a sustained force 6/7 reached gale force 8 at times during the afternoon. At Capel Curig force 9 was recorded at 15 GMT with a peak gust of 68 mph. The wind was strong and gusty through the evening and night. [Rain 0.2 mm; Max 11.8C; Min 5.2C; Grass 3.9C]
6th: A cold front brought heavy rain into W Scotland and Ireland overnight and moved slowly into Wales during the morning. The morning was overcast with a near-gale force S'ly wind keeping strong force 6 during the day only moderating during the evening. There was continuous light rain from 1130 GMT turning moderate from 1500 GMT and stopping by 1700 GMT as the front moved to the SE. A sunless day here although the mountaintops were lit up at sunset. [Rain 3.1 mm; Max 10.6C; Min 8.6C; Grass 7.8C]
7th: The front was over the Welsh Borders at midnight and the morning was fine with cloud decreasing slowly. Pressure 1021 mb was rising in a ridge from high 1030 mb W of the Bay of Biscay. By noon with just 3 oktas of cloud cover it was fine and sunny. There was a moderate NE'ly breeze and the temperature rose no higher than 12.4C. [Rain 0.0 mm; Max 12.4C; Min 4.9C; Grass 2.4C]
8th: With clear sky overnight the temperature on the grass had fallen to 0.4C and there was moderate dew. Pressure had risen to 1031 mb with the high 1034 mb off Lands End. Under 3 oktas of thin cloud in the slightly hazy sunshine at 09 GMT the temperature was 10.3C (dewpoint 6.9C). There was a light air from the SW with stronger gusts enough to move small twigs on the trees.. Feeling warmer with the temperature rising to 15.7C during the afternoon. Some small cumulus clouds formed over the mountains that still had some quite large patches of snow on N-facing cliffs and gullies. It was a clear evening and night. [Lee-on-Solent 17.6C, Camborne 12.7h, Valley 11.5h] [Rain 0.0 mm; Max 15.7C; Min 3.5C; Grass 0.4C]
9th: Pressure had risen to 1034 mb over most of the British Isles. It was a sunny morning with 5 oktas of cloud and very good visibility. Fine and dry everywhere except the N of Scotland where there was a little overnight rain. A dry mostly sunny day here the temperature rising from 11.1C at 09 GMT to 16.0C by late afternoon under thin clouds. A fine evening with little or no wind, but no frost. [Valley 3.7h] [Rain 0.0 mm; Max 16.0C; Min 5.0C; Grass 2.2C]
10th: Again no overnight frost. High-pressure was moving NE and was over the North Sea and Scandinavia 1037 mb. Pressure here was on 1034 mb giving another fine, sunny day in most parts of Britain. Under thin high altostratus cloud, and with a light SE'ly breeze, the temperature at 09 GMT was 13.4C (dewpoint 5.6C this rising to 18.5C during the day. Bright with some sunshine for a time in the afternoon before cloud encroached again by evening with sea mist moving into the Menai Strait. Highest temperatures were in the North, 19.4 at Aviemore and 19.0C at Capel Curig. [Aviemore 19.4C, Capel Curig 19.0C, Glasgow 12.3h, Valley 9.2h] [Rain 0.0 mm; Max 18.5C; Min 5.9C; Grass 1.9C]
11th: Pressure was 1039 mb over Scandinavia and was falling here 1032 mb. With 6 oktas cover of altostratus cloud it was a bright and fine morning. There was a light SE wind. The temperature was 13.2C (dewpoint 7.7C) and the soil surface was drying out in patches. Visibility was good, but hazy. Cooler today with the temperature rising to 15.2C and to just 8.1C in Shetland. The cloud dispersed during the afternoon that was mostly sunny well into the evening. Large fires were seen on the mountains on the mountains at 2100 GMT with the smell of burning gorse reaching Llansadwrn (wind E'ly force 2). {Castlederg 20.4C, Dunstaffnage 13.6h} [Rain 0.0 mm; Max 15.2C; Min 7.1C; Grass 3.8C]
12th: Mostly clear skies again overnight and a sunny, but hazy morning. Pressure 1032 mb was unchanged here, but the high 1037 mb had moved to be S of Iceland. There was a moderate NE'ly breeze and the temperature at 09 GMT was 8.6C (dewpoint 3.5C). By noon with dense smoke haze increasing (dust, wildfires and pollutant aerosols can be the cause) the blue of the sky was pale and the mountains were barely visible and had almost disappeared by afternoon. Despite the sunshine, the day's maximum struggled to reach 12.4C. [Tyndrum 20.3, Dunstaffnage 13.3h, Valley 11.6h] . [Rain 0.0 mm; Max 12.4C; Min 4.4C; Grass 2.4C]
13th: Bright with hazy sunshine and a cool NE'ly breeze. Overnight the temperature on the grass was down to 0.8C with some dew formed. The drying soil on the surface of the bare plot was still damp in patches. Pressure was high 1037 mb to the NW, but had fallen to 1029 mb here. Another cool day with hazy sunshine, paled blue skies and a maximum of 11.4C A weak cold front over Scotland moved S during the day and cloud encroached by late afternoon so that the sky was mostly covered by 1830 GMT giving a dull evening. [Lee-on-Solent 17.5C, Dublin AP 12.6h, Valley 11.5h] [Rain 0.0 mm; Max 11.4C; Min 3.9C; Grass 0.8C]
14th: Pressure was 1025 mb in a ridge from Atlantic-high 1038 mb to the W. The morning was overcast and dull at first with remnant frontal cloud slipping South. There was a moderate NE'ly breeze and the temperature 8.7C rose to just 9.8C during the day. With the cloud breaking up sunny spells developed through the morning while the afternoon was mostly sunny as the cloud cleared. Haze thickened again during the day. Less windy during the evening under a mostly clear sky. {Tyndrum 20.2C, Dublin 12.6h, Valley 10.1h} [Rain 0.0 mm; Max 10.1C; Min 4.4C; Grass 1.8C]
15th: A fine and sunny start to the day with moderate visibility and haze, enhanced by volcanic ash, the mountains were largely obscured. Flights in and out of British airspace were cancelled amid fears of engine damage due to the ash. High-pressure continues to dominate with pressure here 1026 mb and high 1035 mb S of Iceland. There was a moderate NNE'ly wind with the temperature at 09 GMT 8.1C (dewpoint 3.7C). Airflow around the high was responsible for bringing a plume of ash from the Eyjafjallajökull volcano in Iceland towards Britain. Deposits of dust were observed Lerwick, Shetland, during the afternoon. Keeping sunny during the afternoon, with a maximum temperature of 10.3C, the haze thickened with views of the mountains obscured from Anglesey. The evening remained fine with hazy sunshine and the night had mostly clear sky with the temperature on the grass falling to 0.2C. [Shannon AP 12.6h, Valley 12.0h] [Rain 0.0 mm; Max 10.4C; Min 3.7C; Grass 0.2C]

The first 15 days had rainfall of 18.4 mm (25%) and [32%] of average. The mean temperature 8.2C was below and both the decadal (-0.9) and 30-y [-0.4] monthly averages.

16th: Another fine and sunny morning after an overnight touch of ground frost (-0.7C). The temperature at 09 GMT was 10.4C, this exceeding yesterday's highest so 10.4C was the maximum for the past 24-h (09-09 GMT). Pressure was 1031 mb within the high established over the Irish Sea, there was a light E'ly breeze. Visibility was good, but again hazy a combination of pollutant aerosols and volcanic dust. The Met Office reported fine ash from the Eyjafjallajokull volcano had been detected in northern England, the Midlands and the Thames Valley. Falls of dust were reported in Sheffield and as far south as Swindon, Brize Norton, Kent and Chiswick in London, Flight restrictions remained in place over Britain. Somewhat warmer here today, 12.8C by afternoon requiring the opening of greenhouse vents! The white flowers of blackthorn, that come out before the leaves open, were spotted in hedgerows along the road to Benllech. Haze increased through the day being moderately thick with the skies being mostly clear of cloud. Clear skies in the evening with visibility improving views of the mountains were much clearer. A clear night with another touch of ground frost. [Aboyne 18.3C, Dublin AP, 13.3h Valley 12.8h] [Rain 0.0 mm; Max 12.8C; Min 3.5C; Grass -0.7C]
17th: A sunny morning with the temperature 12.0C at 09 GMT. Pressure was 1023 mb in a narrow ridge extending from high 1037 mb over Greenland with low-pressure 990 mb Norway and 998 mb off S Portugal. The breeze still felt cool, but in the hazy sunshine the temperature rose to 17.8C, highest since the 10th. Snow showers were reported in Shetland. The explosive eruptions of the Eyjafjallajokull volcano continued today (see MODIS AQUA satellite image). According to the Icelandic Met Office there were numerous lightning strikes associated with the plume. The cloud height was about 16,000 feet (4876 m), periodically up to 24,000 feet (7315 m) with ash being carried southward. There were reports from many parts of Britain of slight dust deposits from the volcano. {Sutton Bonnington 18.4C, Coleshill 13.9h, Valley 12.8h] [Rain 0.0 mm; Max 17.8C; Min 3.4C; Grass -0.7C]
18th: Almost clear skies again this morning with hazy sunshine and moderate visibility. A cold front over Scotland had brought a return to wintry weather with snow showers making their way southward during the day. Cloudier with moderately high cloud encroaching over Snowdonia later in the afternoon with clear skies remaining over Anglesey. Moderately thick smoke haze and volcanic ash continuing to cover much of Britain and spreading to Europe. With the frontal cloud stalled, just to the N of here, the evening sky was clear at first giving a cool evening with the temperature on the grass falling to 0.3C. Cloud began to encroach by 21 GMT. [Valley 8.9C] [Rain 0.0 mm; Max 12.9C; Min 4.0C; Grass 0.3C]
19th: Mostly cloudy overnight as the frontal cloud moved S; there was mist around dawn, but visibility improved to moderate by 09 GMT. There was a slight deposit of small grey dust particles over 24-h on a cleaned surface. Partly cloudy with a few sunny spells during the morning. Similar in the afternoon with the temperature rising to just 9.8C. Brightening from 15 GMT onwards and mostly sunny during the evening. [Rain 0.0 mm; Max 9.8C; Min 3.8C; Grass 0.8C]
20th: Becoming cloudy with slight showers of rain around dawn in some places, then brightening with some hazy sunshine during the morning. I am grateful to Duncan Brown who alerted me to deposits of greyish white dust on cars in Nebo and Bethesda, Gwynedd, that may have come from the Eyjafjallajokull volcano, and trace deposits of reddish brown dust in Waunfawr may be Saharan in origin. The volcanic dust appears to have moved S in association with the weather front on the 19th. While there has been some dry deposition, larger deposits could have been washed out by showers of rain when and where they occurred.

The HYSPLIT volcanic ash model at the NOAA ARL website was used to confirm the position of the ash plume following eruptions timed at 2100 GMT on the 17th (see MODIS image above) and 1200 GMT on the 18th. The plume headed S taking up to 48-hours to arrive over North Wales between the 19 - 20th before retreating North again. Backward trajectory analyses for Nebo revealed that the ash plume was overhead during the 24-h between 2100 GMT on the 19th to 2100 GMT on the 20th. Trajectories 0600 GMT to 1000 GMT on the 20th, when light showers of rain were reported, were when deposition was most likely. The example trajectory for air arriving at 0800 GMT on the 20th between 1500m and 2500m AGL at Nebo (left) indicates parcels of air over the volcano between 3000m (10,000 ft) and 5000m (16,000 ft) about 24-h previously, earlier and later trajectories were similar.. The reddish brown dust in Waunfawr is likely to have originated from a pool of dust NW of the Canary Islands originating from dust storms in the Sahara. This dust was transported at higher level around the high-pressure over the Atlantic, passing close to Iceland, taking a much longer journey time than the volcanic dust.

Turning cloudier early in the afternoon and becoming thick enough to produce a few spots of dusty rain at 1525 GMT; the temperature reaching just 10.9C in the persistent cool NE'ly breeze. Less hazy by evening with views of the mountains improving. [Valley 6.0h] [Rain trace; Max 10.9C; Min 1.1C; Grass -2.8C]
21st: Fine and sunny. Pressure was 1024 mb in ridge of high-pressure from high 1025 mb N Ireland. Just 3 oktas of cloud cover, and in the fresh NE'ly breeze the 6.8C air temperature felt chilly. There had been trace amounts of both grey and light reddish brown dust over 24-h on a clean surface. There was some precipitation to the N overnight with snow showers in N Scotland and over the Highlands. Despite plenty of sunshine through the day the air temperature failed to reach double figures reaching 9.9C. [Lee-on-Solent 14.8C, Prestwick 13.4h, Valley 8.3h] [Rain 0.0 mm; Max 9.9C; Min 2.4C; Grass -0.3C]
22nd: Yesterday was the 15th day without measurable rain and qualified as an absolute drought. The terminology introduced by G. J. Symons in 1887 is no longer used officially, it required a minimum of 15 days none of which was credited with 0.2 mm, or more. Overnight the air temperature fell to 0.7C and on the grass the -4.2C was lowest of the month. Pressure 1020 mb was falling and low 1002 mb S Norwegian Sea brought a cold front on to N Scotland during the morning. Wintry showers continued to affect N Scotland, but here it was much of the same with good spells of sunshine with the cool NE'ly wind. [Chivenor 15.0C, North Wyke 13.2h, Valley 11.1h] [Rain 0.0 mm; Max 11.6C; Min 0.7C; Grass -4.2C]
23rd: Overcast at 06 GMT the moderately high cloud thinning and dispersing as the sun got higher in the sky as 09 GMT approached. A warm front lay over Scotland and to the N snow showers continued in Shetland and the Highlands, but rain elsewhere. It was dry here with thin cloud and mostly weak, hazy sunshine, for a change the wind direction was S'ly and with the temperature rising to 15.4C the day was much more pleasant. Also observers spotted the first swallows of the season, their arrival perhaps boosted by the S'ly wind. {Northolt 18.1C, South Uist 16.0 mm, East Malling 13.3h, Valley 7.3h] [Rain 0.0 mm; Max 15.4C; Min 3.0C; Grass -1.5C]
24th: Broken cloud and a light ESE'ly breeze and a temperature of 12.5C (dewpoint 3.6C, 54% RH) at 09 GMT. Dull at first soon brightening with weak hazy sunshine the temperature rising to 18.8C, highest of the month. {London, St. James Park 21.3C, Stornoway 8.0 mm, Manston 12.5h} [Valley 15.6C, 6.5h] [Rain 0.7 mm; Max 18.8C; Min 5.0C; Grass 0.6C]
25th: A shower of rain (0.7 mm) at 0230 GMT broke the 16-day drought, but by 09 GMT the ground was again partly dry. Droughts are rare here, it is necessary to look back to 1997 to find a longer drought in April (17-days, 3 - 21). In May 2004 there was an 18-day drought in Llansadwrn between the 9th and 26th. [Rain trace; Max 15.2C; Min 9.9C C; Grass 7.9C]
26th: Mostly cloudy and dull at first, but brightening later. High 1030 mb was centred over the western approaches to the English Channel with pressure here 1025 mb. Another fine and dry day becoming sunny by afternoon the temperature rising to 17.1C; light winds during the morning strengthened to force 5 S'ly by 18 GMT. At 21 GMT the sky was mostly clear with good visibility. [Rain 0.0 mm; Max 17.1C; Min 8.1C; Grass 5.0C]
27th: A fine morning, but becoming increasingly dull. At 09 GMT the temperature was 12.2C (dewpoint 9.7C) with good visibility. Pressure was 1027 mb close to high 1029 mb N France, but frontal cloud associated with low 991 mb S of Iceland lay over western Britain. By noon it was brighter as cloud moved eastward and the afternoon was fine and sunny the temperature rising to 17.3C. [Rain 0.7 mm; Max 17.3C; Min 7.1C; Grass 2.8C]
28th: After a light shower of rain around 04 GMT, associated with a weak cold front, it was a fine morning with plenty of sunshine. At 09 GMT there were 5 oktas of altocumulus (with a few lenticular clouds in the lee of Snowdon), cirrostratus and cirrus clouds with very good visibility. There was a gusty fresh S'ly wind and the day continued breezy with the temperature rising to 18.3C during the afternoon. . [Rhyl 20.9C, Capel Curig 17.7C] [Rain 0.1 mm; Max 18.3C; Min 11.8C; Grass 10.0C]
29th: A dull morning with skies overcast. Pressure was 1010 mb with a low heading N over the Channel into SW England and S Wales. A band of rain reached mid Wales during the day, but kept SE of the Snowdonia Mountains keeping dry here. Late afternoon was brighter with a few glimpses of sunshine during the evening before a little showery rain from 2230 GMT to about midnight. {Hawarden 14.3C, Valley 1.0h} [Rain 0.4 mm; Max 12.5C; Min 9.8C; Grass 9.8C]
30th: After a shower of rain around 02 GMT there was a clearing sky up to 09 GMT with altocumulus clouds above the weather station. Cumulus clouds were building over the mountains to the S and soon the morning turned cloudier. Showery rain spread NE across N Wales, there were a few spots here from 11 GMT, slow to wet the dry ground at first, and slight rain from noon until around 14 GMT. Later the sky began to clear allowing a little sunshine with a few more spots of rain around 18 GMT. [Rain 0.5 mm; Max 13.6C; Min 7.6C; Grass 5.2C]

The month ended with a rainfall total of 20.8 mm, lowest since 1984, (28%) and [36%] of average ranking 7 since 1928. The mean temperature was 9.1C, lowest since 2006, (-0.1) based on the decadal average and [+0.5] of the 30-y average indicating a continuing warming trend. It was sunniest since 2007, the 222.9 h duration recorded at Valley was the second highest on the Anglesey record since 1930, (137%) and [142%] of average. The sunniest day on the 16th had 12.8h, there were no sunless days.

May

1st: A mostly cloudy morning with good, but hazy visibility. There was moderate to heavy dew on the grass, but no frost with the minimum 2.1C. Pressure was 1009 mb with low 1008 mb off NW Ireland and frontal cloud to the North. There were shower troughs to the West and there were light showers over parts of Snowdonia in the morning with bands of heavier showers over mid Wales and S Snowdonia during the afternoon. Here although forecast had indicated heavy rain later the day was fine and dry with the sun occasionally breaking weakly through with no bright sunshine. [Rain 0.2 mm; Max 11.6C; Min 5.0C; Grass 2.1C]
2nd: A bright morning with high cirrus cloud dominating with a few small cumulus mainly to the South and cirrostratus to the West. With no substantial rainfall bare soil was looking bone dry, but lawn grass and fields were looking very green. Hedges and trees are leafing up, the beeches with their bright light green leaves are well ahead along with horse-chestnuts. Sycamores remain slow to leaf while ash and elm are in flower with little or no leaves. Bud scales have started to fall and with gusts of wind they sometimes resemble snowflakes. The day was mostly sunny and with a cool NE breeze off the sea the temperature rose to 10.3C. During the evening showers moved in across Anglesey and NW Wales off the Irish Sea. From 2230 GMT until after midnight, as the air temperature dropped to 3.7C, there was wintry precipitation, including snow pellets. [Pptn 0.7 mm; Max 10.3C; Min 6.0C; Grass 4.5C]
3rd: Another bright and sunny morning with very good visibility in clear air, there was a sprinkling of fresh snow on the mountaintops across the range from the eastern Carneddau, low on the cliffs of the N-facing Black Ladders as low as 2250 ft, centrally on the summits of Y Garn and around Yr Wyddfa in the West. Cumulus clouds were being blown along briskly on the fresh NE'ly breeze. Pressure was 1028 mb with high 1036 mb W of Ireland and complex low-pressure over Europe to the East. This continued the flow of cool air from the arctic with showers affecting E-facing coasts of the UK. The Mediterranean was keeping uncharacteristically unsettled with low-pressure over N Africa. The day was mostly sunny on Anglesey with cumulus clouds persisting over Snowdonia. There are now plenty of bluebells flowering in the wood .The evening was sunny with a clear sky at 21 GMT. [Rain 0.0 mm; Max 11.1C; Min 3.7C; Grass 1.5C]

4th: With a mostly clear sky overnight the temperature on the grass dropped to 0.2C and there was moderate dew. A sunny morning on Anglesey with scattered fair weather cumulus clouds; the mountains were mostly cloud covered. Pressure was 1030 mb with the high 1036 mb W of Ireland and low 990 mb over the western Mediterranean. There was a force 3/4 N'ly breeze and visibility was good with slight haze. Soil moisture levels had fallen to 36% and soil under grass was dry and crumbly. The afternoon had fewer cumulus clouds over Anglesey at first while they persisted over Snowdonia. By 16 GMT the sky was cloudier and becoming increasingly hazy. [Rain 1.6 mm; Max 11.6C; Min 3.2C; Grass 0.2C]
5th: Overcast with moderate fog and heavy drizzle from 0430 GMT easing by 09 GMT to light drizzle. There were trace deposits of dark-grey volcanic dust. Pressure 1024 mb had fallen with high 1033 mb W of Ireland and low with frontal wave over Italy. A frontal wave was over the Isle of Man with a warm front hanging SW-ward over Anglesey and Cardigan Bay. Fog was lying to low level in the Menai Strait and slight drizzle continued through the morning into the afternoon when there was a spell of light rain with further deposits of dark-grey volcanic dust. Ash dispersion from eruptions of the Icelandic Eyjafjallajokull volcano, being a point source of emission , is very dependent on the local direction of air flow. Forward trajectory analysis, using HYSPLIT at the NOAA ARL website, indicated that parcels of air over the volcano at 06 GMT on the 4th reached western Britain and Wales on the 5th between midnight and 06 GMT today. Air over the volcano at high levels (10,000 m) arrived first, lower levels (1000 m) took longer to reach here (and then traveled further into S Europe) partly accounting for the spread of deposition observed during the day. Rain ceased and the cloud thinned by 16 GMT; there was some weak sunshine breaking through at 1730 GMT. There was little or no wind. [Rain 3.4 mm; Max 11.5C; Min 7.2C; Grass 5.2C]
6th: As the fronts moved S there was a spell of light rain from 0200 GMT until 06 GMT with drizzle and fog up to 09 GMT. A moderate deposit of dark grey dust was collected at 09 GMT. Backward trajectories using HYSPLIT at the NOAA ARL website indicated that air during the spell of rain came from the vicinity of the volcano, the example (right) is at 06 GMT for air arriving over Llansadwrn between 1500 and 2500 m AGL. A light NE'ly breeze picked up, but the fog persisted through the morning until 1430 GMT when it began to lift. Soon the sky cleared and the rest of the afternoon was sunny with a cool NE'ly breeze. There were a few cumulus clouds mainly over the mountains of Snowdonia and it was cloudier after 21 GMT with a shower of rain at 2200 GMT. {Helens Bay 16.5C, Milford haven 14.5C, Mumbles Hd. 10.8 mm, Tiree 12.6h, Valley 5.0h} [Rain 0.8 mm; Max 13.3C; Min 8.0C; Grass 5.5C]
7th: Overcast sky after midnight, but clearing after a slight shower of rain around 08 GMT. pressure was 1016 mb with remnant occluded frontal cloud along the spine of Britain. High 1020 mb was SW Iceland and with low-pressure 1002 mb over Europe we were still in a cool NE'ly flow of air from Arctic regions. There were cumulus clouds over the mountains, but on Anglesey it was a mostly sunny day. Cloudier by evening with a pale sunset. {Hawarden 14.4C, Valley 8.9h} [Rain 0.0 mm; Max 12.2C; Min 5.9C; Grass 4.0C]
8th: Pressure had risen to 1017 mb, high 1031 was SW Iceland and low 999 mb was over the Azores with weak low-pressure centres scattered across the Mediterranean and N Africa. Slow-moving frontal cloud lay over S England and the Channel with patchy rain keeping to the S of the Snowdonia Mountains. The day was fine and dry here with sunny or weak sunshine through until the evening. The persistent moderate to strong NE'ly wind, directly from the Arctic regions, felt cold in the shade, but in a sheltered spot the 12.0C maximum was pleasant enough. The best place to be was on the West coast, less windy and a chance for the air to warm a little crossing the island reaching 13.4C at Valley. The evening and night were clear skied with the wind moderating at dusk. [Rain 0.0 mm; Max 12.0C; Min 7.3C; Grass 6.3C]
9th: With pressure steady on 1017 mb it was a fine and sunny morning with a few fair-weather cumulus clouds moving along on the gentle NE'ly breeze. Slight dew on the grass with the minimum thermometer reading 0.5C. The slowest the air temperature in the screen reached was 3.2C. Currently (090 GMT) it was 8.5C (dewpoint 3.7C) and this was to rise to a modest 11.1C during the sunny afternoon (clear blue sky at first, hazier and murky later). Butterflies were around the garden mostly orange tips, holly blues and the odd peacock. Fledged robins were seen, the first of the season. Blue tits will not be long as frantic feeding is taking place in one of the nesting boxes in use. [Rain 0.0 mm; Max 11.1C; Min 3.2C; Grass 0.5C]
10th: A cloudy morning with a mixture of cumulus and stratocumulus clouds. Pressure was 1014 mb in a weak ridge of high-pressure while the Atlantic-high was intensifying (1035 mb at noon). During the morning there were a few sunny spells (very blue sky), but towering cumulus clouds were seen to the SE with precipitation over some of the mountains to the E of the range. A band of light rain was slow-moving to the NE and more dark clouds moved across the N Wales coast early in the afternoon. A very light NE'ly breeze at first picked up during the day to force 4/5 by late afternoon. It was another dry day here with long spells of sunshine later in the afternoon. After 18 GMT there was thin cloud with hazy sunshine. {Solent 15.9C, Milford haven 13.2C, Manston 10.6h, Valley 7.7h} [Rain 0.0 mm; Max 11.4C; Min 5.9C; Grass 3.8C]
11th: Another chilly, but frost-free night mostly cloudy at dawn and starting to clear before 09 GMT. There were moderately developed cumulus clouds moving in off the Irish Sea on a moderate NNE'ly wind. These produced a sprinkling of snow as low as 1500 ft on the central Carneddau, most on the top between C. Dafydd and Penyrole-wen, and in Cwm Idwal. Pressure was 1015 mb with the Atlantic-high 1037 mb slipping S to just below 50° N at midnight. Pressure was low 1004 mb over Brittany with an occluded front lying from Cape Finisterre to S Baltic. On the southern French coast between Cannes and Nice an unseasonable storm, with reported 8-10-m high waves, caused a lot of damage and closure of part of the Promenade des Anglais in Nice. Showers kept away from here and there were some sunny spells in the morning. In the afternoon longer spells of sunshine, with a clear blue sky and a few passing clouds the temperature rose to 10.2C lowest of the month, the wind moderating at times only to return again later. Clear sky at dusk with the temperature on the grass falling to -0.5C. [Pptn 0.7 mm; Max 10.2C; Min 3.2C; Grass 1.0C]
12th: Showery precipitation from 0130 to almost 0300 GMT left a few faint marks on the hailometer indicative of snow pellets. The overnight minimum temperature was 2.5C and on the grass -0.5C, both lowest of the month. Showery precipitation off the Irish Sea from 0730 GMT was sleety with more sprinklings of snow seen on the mountaintops. The snow today had fallen mostly on C. Llewelyn and towards Foel-grach and together with remnants of yesterday's falls sufficient to record >50% cover above 2800 ft. Pressure was 1016 mb with the Atlantic-high 1035 mb at 48° N 35° W. Pressure still remains low 1006 mb over the Mediterranean. Cumulonimbus were seen with further wintry showers falling on the mountains during the morning. Here, some sunny spells in the persistent NE'ly with convective clouds in the vicinity through to the afternoon. Heavy showers were reported on the mainland near the mountains. By 1800 GMT the sky was clearer except for the mountaintops, and it was less windy before dusk. There was a fine view of the ISS, now the largest bright object in the sky apart from the moon, passing slowly at 45° NW to SE at 2200 GMT in clear sky. [Rain 0.0 mm; Max 11.3C; Min 2.5C; Grass -0.5C]
13th: More or less a clear sky at 06 GMT with a minimum temperature of 2.6C; with dew on the grass that had dried off by 09 GMT. It was also cloudier, 3 oktas and a change of wind direction being SSW'ly force 4. Completing the obs a dark cumulus cloud approaching from the W brought a gusty wind and a few spots of rain at 0915 GMT. The Atlantic high had moved a little further S to 47° N 33° W and there was a low 992 mb over SE Iceland. Pressure remained low over the Mediterranean with low 1004 mb over Italy. Volcanic ash kept to the W and N of Britain, with a tongue as far as Spain. A mostly sunny day with scattered cumulus reducing to a few by the afternoon when frontal cloud was seen encroaching from the north-west reaching here by 1800 GMT. New potatoes from Llanbedregoch were on sale on the roadside for £3 per kilogram. Jersey potatoes have been reported as being in short supply this year because of the dry weather. [Rain 1.9 mm; Max 13.4C; Min 2.6C; Grass -0.4C]
14th: There was light rain from 0100 GMT to 0500 GMT turning to drizzle and slight showers ongoing at 09 GMT. Overcast sky with lowish ragged stratus with mist and rain in sight on slopes of mountain in the West. To the east it was clear with very good visibility, this soon changing as the low cloud moved across the range. The morning kept dull and overcast, but the the sky began to clear at 15 GMT and the rest of the afternoon and evening had clear sunshine. Still cool for May the maximum reaching 12.6C, but in Liscombe in Devon the maximum was 7.4C. Scattered clouds began to encroach at 22 GMT. {Gravesend 16.7C, St. Bees Hd. 26.4 mm, Rhyl 11.8 mm, Valley 9.1h} [Rain trace; Max 12.6C; Min 6.5C; Grass 5.9C]

It was a dry first 15-days with 11.9 mm (16%) and [21%] of average, and with temperatures well below even the 1971-2000 average. The mean maximum was 12.0C (-3.6) and [-4.0] and the mean minimum 5.0C (-3.2) and [-2.0].

15th: Overcast at times during the night, occasional broken cloud, overcast and murky at 0600 GMT with poor visibility. Visibility had improved by 09 GMT with 5 oktas cover of developing cumulus clouds. Calm or variable light winds at the surface here, but generally there was a NW'ly flow bring the clouds overhead. Pressure was 1017 mb with Atlantic-high 1031 40° N and 24° W. Low 997 mb was NW of Rockall, low 987 mb was over the Baltic and low 990 mb over the Adriatic and producing much sharp wave action on the Mediterranean Sea. The morning was dry and had some sunny spells between the passing clouds. The afternoon was sunnier with the temperature rising to 15.5C. By evening with a frontal wave over Ireland moved across the Irish Sea and was here by midnight. [Rain 2.6 mm; Max 15.5C; Min 5.1C; Grass 2.0C]
16th: Light rain from midnight to just before 03 GMT bringing a welcome 2.6 mm of rain. It had wetted the soil, the grass had greened up, but was evaporating with concrete already dry. Soil moisture was down to 34% DW, it will take a little more rain to make a lot of difference. It was a mostly cloudy morning with cloud building up against the mountains was slow to clear. The afternoon was sunnier with the temperature rising to 16.3C before a cloudier, and rather murky evening with a paled blue sky the result of more volcanic ash overhead. Flight restrictions in British airspace were again in force in the north-west. {Sennybridge 14.5C, Valley 9.6h}[Rain 0.0 mm; Max 16.3C; Min 4.8C; Grass 2.0C]

At Tywyn Aberffraw the last traces of water in the pool slacks left from the rains in March was fast disappearing. The mature willow slack above looked very green, as did some of the other slacks, where creeping willow was beginning to flower . The fixed dunes, however, looked very dry. Usually at this time of year they are green with mosses, but with recent dry weather this is not so. There were lots of common blue butterflies around , the female is brown with a light dusting of blue near the body. Few plants were seen in flower, there were a few dune pansies . It was a different matter on rocks bordering the beach where the sea pink (thrift) was in full flower on the rocks amongst colorful orange, grey and black lichens. Also on a rock, although it also grows on sand, was sea sandwort and here is the flower in close up .

It was the sunniest May at Valley on the Anglesey record with 271.9 h duration [(140%)] of average, despite having 2 sunless days beating the previously highest 1977 (Kipp & Zonen adjusted data). The sunniest day was on the 23rd with 14.7h. In Llansadwrn the 28.6 mm rainfall, lowest since 1998 (25.3 mm) ranking 8 since 1928, was (39%) and [50%] of average. The mean temperature was 10.8C and despite 4 days >20C was (-1.1) and [-0.7] of average. With 133.9 mm rainfall it was the driest spring since 1990 (80.2 mm lowest on record since 1928) ranking 7.

June

1st: Light rain from 0100 - 0530 GMT then some drizzle accumulated 7.5 mm that was credited to the 31st May (see above). At 09 GMT the sky was still overcast, but the cloud was thinning and was lifting from the lower slopes of the mountains that were still looking misty. Pressure was 1014 mb with high 1018 mb over the North Sea while low 988 was SE Greenland. An occluded front over Anglesey was slow-moving towards Merseyside arriving there about 1400 GMT. The morning kept dull and overcast, dry at first then with the cloudbase lowering again some drizzle came along before noon, reducing visibility from good to poor, before 30 minutes of light rain to 1230 GMT although nothing was evident on the rainfall radar. Soon the sky began to clear and there were some sunny spells. The grass looked a little greener after the rain and the vegetables had perked up too. The temperature rose to 13.9C, lowest of the month. By the end of the afternoon the sky was clear overhead and later shallow fog formed on the fields this persisting overnight. Brown long-eared bats were seen flying around the weather station at 21 GMT. {Kinloss 20.0C, Milford haven 17.7C} [Rain 1.0 mm; Max 13.9C; Min 10.4C; Grass 9.4C]
2nd: After shallow fog at 05 GMT cleared it was a fine and sunny morning with just a few small cumulus clouds seen over the Snowdonia Mountains. The morning was mostly sunny with the temperature rising to 21.7C before a NE'ly breeze off the sea came along. The wind was initially S'ly, but by afternoon convergent cloud had formed (sea breeze front) over the weather station as the NE'ly strengthened. There was a rapid fall in temperature to 16C that was maintained through the afternoon although the sky cleared again later. The evening was sunny. [Rain 0.0 mm; Max 21.7C; Min 8.2C; Grass 4.6C]

Bodnant Garden dates from 1875 and is one of the finest gardens to see specimen trees in a natural setting, including over 100-y old giant American Californian Redwoods (146 ft) and Oregon Douglas Fir (158 ft) and, at this time of year, flowering rhododendrons and azaleas many varieties of which were grown at Bodnant all growing well in our climate and soils . Established by Henry Pochin, an industrial chemist, the garden was given to the National Trust in 1949 by Henry McLaren, 2nd Baron Aberconway, and is managed by his descendants that retained the house (1792) . The Lily Terrace has a fine view of the E-facing slopes of the Carneddau Mountains . Many of the trees and Rhododendrons grow on the sides of the Hiraethlyn River valley , cut by melt-water from the overflow of an ice-dammed lake during the latter stages of the last Ice Age. The Denbigh type soils, typical of a large part of Wales, are slightly acidic being low in calcium and other nutrients and suit the growing of califuge plants including Rhododendrons and woodland. It was a warm sunny day and parts of the garden were perfumed by the aromatic leaves and scented pure white flowers of Mexican orange blossom . The garden recently described, unfairly I thought, as 'an old man's garden', is being restored and re-developed in parts by a team of gardeners under Head Gardener Troy Smith. To have started planting Bodnant over 100-y ago required vision: To maintain the garden today needs a lot of work, make a visit soon and see for yourself.

3rd: With scattered clouds, a light SE'ly breeze and sunshine it was a warm morning with the temperature at 09 GMT already 20.0C (dewpoint 13.0C). pressure was 1023 mb with high 1025 mb over the Wash and S North Sea. Visibility was good with smoke haze developed. The day had some good spells of sunshine and the temperature by afternoon reached 23.3C; cirrus kept to the NW and convergent cloud formed over central Anglesey today keeping the sky clearer here. {Hawarden 23.5C} [Rain 0.0 mm; Max 23.3C; Min 11.5C; Grass 6.8C]
4th: Some high cirrus clouds early had cleared by 09 GMT. The morning was mostly sunny with moderate smoke haze developed. A few patches of moderately high clouds passed over around noon. The breeze kept S'ly all day and was strong enough to hold back the cool NE'ly off the sea so that the temperature rose to 24.0C during the afternoon. The first comma butterfly of the season was spotted in the garden. The evening was sunny too and 'big ears' was flying around the weather station when it was still quite light at 2100 GMT; there were some large moths in the garden no doubt an attraction for the bats. {Northolt 27.9C, St. Athan 24.7C} [Rain 0.0 mm; Max 24.0C; Min 12.5C; Grass 7.6C]
5th: A cloudier morning with altostratus and cirrus although cover had reduced to 5 oktas at 09 GMT. Visibility was good with persistent smoke haze. At times the day was overcast with cloud that was thin enough for weak sunshine at times. By evening the cloud was thicker, but there was no rain. [Rain 0.0 mm; Max 20.1C; Min 11.5C; Grass 7.5C]
6th: At midnight thicker frontal cloud had encroached and by morning low cloud and drizzle began to affect NW Anglesey. A cold front associated with a shallow low over London brought storms and heavy rain showers across W and N France into Belgium during the morning and Spain, Germany and S France by afternoon. Dry and bright here at first with a little light rain from noon enough to wet the ground, but not enough to restore soil moisture levels. Soil moisture measured on the 5th was 25.8% dry mass with surface soils dry and powdery. Some sferics were recorded in SW Scotland and to the S over Wales, the Midlands (with some heavy showers) and SE England during the afternoon. The evening was dull and damp. [Rain 0.9 mm; Max 17.4C; Min 10.6C; Grass 9.1C]
7th: Overcast skies at first becoming brighter with glimpses of sunshine later. Pressure was 1011 mb with a low 1000 mb SW Ireland pushing a warm front towards the Irish Sea. The temperature at 09 GMT was 15.3C (dewpoint 12.4C) and this rose to 18.0C in the afternoon that had some warm sunshine in a S'ly breeze. On the shore at Red Wharf Bay, where the salt marsh was a blaze of pink flowering thrift (click on panorama above), there was a cooler NE'ly breeze off the sea, but 19.9C was recorded in Pentraeth.. Dark clouds built up S of the Snowdonia Mountains and there were a few spots of rain before continuous light to moderate rain set in from 1700 GMT; rain was heavy for a while around 2230 GMT. [Hawarden 19.3C, Pembrey Sands 22.6 mm, Mona 19.2 mm, Valley 1.2h] [Rain 14.3 mm; Max 18.0C; Min 10.8C; Grass 8.8C]

In Red Wharf Bay there is a salt marsh (open panorama above) that has typical hummock and channel formation. Plants (halophytes) that grow on salt marshes are tolerant of salt water to a greater or lesser degree. On a rising tide the sea flows into the channels, and unless it is a spring tide the tops of hummocks rarely become inundated with salt water . The tops of the hummocks have a flora including sea pink (thrift) and sea plantain, but both also grow on mountains too . Smaller and sometimes missed, growing on the driest parts of the marsh, is the sea milkwort that is a member of the Primulacae . The plant also occurs in saline habitats in Staffordshire and Worcestershire.

8th: Moderate rain continued until 0500 GMT and 14.3 mm was accumulated in the rain gauge over 12 hours. This was the most since 30th March (21.3 mm). A dull morning, but no more rain. With a low over the Bristol Channel pressure here was 1000 mb with an occluded front stretching from Anglesey to Kent. Visibility was very good, cloud hugging the mountaintops occasionally revealing the last surviving patches of snow . Brighter around noon with a few glimpses of sunshine and some longer spells in the afternoon; dark clouds associated with showers S of the mountains kept away. During the evening a line of low stratiform cloud stretched along the line of the Menai Strait with the mountaintops remaining clear. [Rain 0.0 mm; Max 18.0C; Min 12.2C; Grass 11.9C]
9th: Overcast and dull at first with poor visibility in haze. There was some breaking of the cloud overhead at 09 GMT and it was for a time brighter, but there was little if any bright sunshine. Pressure was 1003 mb with low 997 mb over Cape Finisterre the low-pressure extending 1001 mb to SW England. Complex frontal systems lay over Britain and W Europe. There was showery rain in mid Wales, N Ireland and NW Scotland. The afternoon was bright at first, with the sun seen occasionally through thinner patches of cloud, then the cloud thickened bringing slight drizzle and a shower of light rain from 1515 to 1530 GMT amounting to just 0.6 mm overall. . A dull, but dry evening. [Rain 0.6 mm; Max 15.6C; Min 12.2C; Grass 11.5C]
10th: Not a lot of change in weather overnight that was mild with a minimum of 11.8C and 11.3C on the grass. There was a moderate to fresh NE'ly breeze and soil, concrete and grass were all dry. Pressure had risen 1012 mb with high 1022 mb N of Scotland and low 992 mb anchored in the Bay of Biscay. A band of frontal cloud stretched over the Irish Sea to the North Sea. Cloud hung low on the mountaintops, but thinned here with the morning becoming bright with some glimpses of sunshine. In the afternoon the cloud began to disperse giving clear sunshine into the evening here although some cloud persisted over most of the mountaintops. [Rain 0.0 mm; Max 15.7C; Min 11.8C; Grass 11.3C]
11th: Shallow mist formed on the fields at dawn and cloud moved across soon after so that at 09 GMT we were back to an overcast sky. The grass was very wet with dew and mist droplet deposition, but the soil surface and concrete were dry. The grass minimum temperature had fallen to 5.9C, and the soil temperature at 5 cm depth was 14.5C. The Biscay low was filling 1001 mb, but going nowhere, with pressure here 1011 mb continuing to rise. Brightening during the morning, but hazy moderate visibility and cloud on the mountaintops persisting. A rapid change to clearer good visibility just after noon sent me hastily with binoculars to my snow observing position. The tops had been obscured since the 8th and I was able to confirm that the snow-patches in gullies between Foel-grach and Carnedd Llewelyn had not yet melted, but the smaller one was now very small, just visible with high-power binoculars, and likely to disappear soon . This is the latest date for snow to last on the Snowdonia Mountains in recent years. Sunshine here into the evening but cloudier on the mountains. Sunshine is not good for the NW-facing snow patches. [Rain 0.0 mm; Max 16.6C; Min 8.6C; Grass 5.9C]
12th: A bright morning, but convective clouds increased up to 09 GMT (5/8). Pressure had risen 1017 mb and we still had the cool moderate NE'ly breeze although the general airflow was NNW'ly. Sunny spells during the morning with the sky almost clear during the afternoon. While flowering plants have been outstanding this year, butterflies are low in numbers. Earlier holly blues and orange tips were frequent, but we have seen only individuals of peacock, red admiral, comma and speckled wood. By 1700 GMT frontal cloud began to encroach and had already brought rain into N Ireland and the Western Isles of Scotland. Though cloudy the evening to midnight remained dry. {Valley 12.3h, Mumbles Hd. 19.2C} [Rain 0.4 mm; Max 15.0C; Min 9.8C; Grass 8.2C]
13th: We had a shower of rain around 0200 GMT with just 0.4 mm caught in the rain gauge. A dull start to the day with a few small spots of rain on the window at 07 GMT. The windvane indicated a change in direction of wind to SW, a ridge 1015 mb began to move into S Britain from large Atlantic-high 1032 mb N of the Azores. The Biscay low had moved towards Gibraltar, but had filled and was losing its identity over the Mediterranean. But, a thundery low 1010 mb developing over the Western Isles of Scotland, with associated frontal cloud, was over Britain and the Irish Sea. At 09 GMT the chiffchaff was still singing together with 2 blackbirds, but birdsong has fallen off. There are lots of fledglings about, families of blue and great tits visit the feeding stations. Two families of woodpeckers also visit (the second of the season), the parent (female right) shows the fluffy youngster with red cap (left) how to feed on the peanuts. Males often do this; birds of other families are not tolerated although we have more than one feeder squabbles develop. A wren is sitting on a late clutch of eggs in a nest, previously built by the male, on top of an unused swallow nest under the eaves of the house above the front door, and holding up maintenance work! Bands of showers in the N began to move SE during the day, the first was at 1130 GMT, interspersed with a little sunshine. During showers at 1625 GMT thunder was heard to the SE of the station. In Llanfairfechan at the same time there was thunder and 'ferocious' ice pellets for a few minutes; thunderstorms and heavy downpours were reported in parts of the Midlands eastwards during the evening. By evening the wind had veered to the NE, giving a fresher feel. At 2100 GMT with a clearing sky it was still light enough to read thermometers, but soon became cloudy again with a shower of rain at 23 GMT. [Rain 4.4 mm; Max 15.5C; Min 9.8C; Grass 8.1C]
14th: No more rain after midnight; variable amounts of cloud with some sunshine breaking through before 09 GMT. There was a moderate to fresh NE'ly wind and already soil and concrete were dry. Pressure 1020 mb was rising with the Atlantic-ridge (high 1031 mb N Azores) beginning to dominate. Yesterday's low was over N France and moving S. Increasingly sunny through the day with cloud lingering over the mountaintops. A small tortoiseshell preferring full sunshine and a speckled wood preferring dappled shade on the edge of the wood were seen. A fine evening with the wind lessening. [Rain 0.0 mm; Max 15.6C; Min 10.5C; Grass 9.0C]
15th: A fine and sunny morning with very good visibility that enabled confirmation that the snow-patch, in a deep gully between Foel-grach and Carnedd Llewelyn, had survived another day. The day kept mostly sunny with few clouds and with a light to moderate NE'ly breeze the temperature was pegged to 16.8C. [Rain 0.0 mm; Max 16.8C; Min 8.5C; Grass 4.8C]

With 11 of the first 15-days dry rainfall of 21.6 mm was running 34% of the average for the month. The mean temperature was 14.2C (-0.1) and [+0.6] of average..

16th: Overnight a clear sky allowed the temperature on the grass to fall to 5.5C so there was some dew. Another fine and sunny morning with 6 oktas cover of high cirrus cloud and, unusually for here many contrails some expanding forming cirrocumulus. Visibility was very good with slight haze and with persistent, but lighter NE'ly winds off the sea the temperature rose to 18.3C during the afternoon. [Glasgow 23.5C, Pembrey Sands 22.1C, Hawarden 20.9C, Capel Curig 19.8C, Valley 19.6C, 14.3h, Aberporth 15.7h] [Rain 0.0 mm; Max 18.3C; Min 8.6C; Grass 5.5C]
17th: A cloudy morning at first, but after 09 GMT began to burn away to give a sunny day on Anglesey although cumulus clouds persisted over the Snowdonia Mountains. The temperature rose to 18.8C in the force 3/4 NE'ly breeze. If you found a sheltered spot it felt a lot warmer. The growth of grass at the weather station this year to this date (2. 8 tonnes per hectare) has been the lowest since before 2004 (7.2 tonnes per hectare) due to a combination of low temperatures in the spring and low rainfall. Soil moisture today was 26% dry mass, well below the 72% saturated water percentage and low enough to limit grass growth, but above the permanent wilting percentage of 15%. In parts of the island grass on shallow soils around rocky outcrops and roadside verges has looked yellowish brown for a week or two. During the evening visibility reduced to moderate to poor and the sky looked very murky. [Rain 0.0 mm; Max 18.8C; Min 12.0C; Grass 8.5C]
18th: At midnight with low 1003 mb over the Baltic associated frontal cloud over Scotland was moving S and began to encroach here by 03 GMT when low mist formed on the fields turning to a 'dry fog' by 06 GMT. At 09 GMT fog was lingering in mountain valleys with mountain tops in the clear, while visibility had improved to moderate here. Grass, concrete and soil were all dry, a dry or non-wetting fog has a very small droplet size and does not wet anything. Pressure was 1023 mb influenced by the Atlantic-high 1030 mb, a weak cold front was just to the North, but a detached warm front lay to the West. The sky was overcast with the air temperature 14.2C (dewpoint 12.0C, RH 87%) and soil temperature at 5 cm depth 18.0C. By 1045 GMT the cloud had thickened and there were spots of rain for about 15 minutes, these evaporating and not wetting the ground. The afternoon was overcast at first, brighter later and as the cloud moved further S began to clear around 17 GMT. [Rain trace; Max C; Min 9.0C; Grass 6.5C]
19th: Mostly cloudy around 06 GMT and beginning to clear by 09 GMT with fair weather cumulus clouds moving from the N across the sky. Winds were strong on the North Sea around low 993 S Sweden. Showers affected the East coast through the day, but here cloud cover reduced and visibility improved to very good by the afternoon although the NE'ly breeze was cool with the highest temperature rising to 13.3C. In slight haze I could no longer see the diminishing snow-patch on the Carneddau without the aid of binoculars, but it was still there during the afternoon. A fine sunny, but cool evening. [Rain 0.0 mm; Max 15.2C; Min 8.7C; Grass 5.5C]
20th: With the sky clearing after 06 GMT it was a fine and sunny morning. The temperature at 09 GMT had reached 15.2C, exceeding yesterday's highest temperature. With high 1026 mb to the W over the Atlantic, pressure here was 1023 mb There were a few cumulus clouds during the morning, less of them in the afternoon before some patchy moderately high cloud moved across later in the afternoon. Today's temperature reached 17.0C. Visibility was good with slight earlier haze clearing. After 1800 GMT the sky was mostly cloud covered. [Rain 0.0 mm; Max 17.5C; Min 7.2C; Grass 3.8C]
21st: With just 2 oktas cloud cover at 09 GMT and a light SE'ly breeze the temperature had risen to 17.5C, the maximum of the past 24-h. Scattered mostly moderately high clouds during the day and in the sunshine the temperature reached 23.6C. The evening was bright with weak sunshine as some cloud encroached from the West, this clearing later. {Castlederg 26.5C, Hawarden 23.1C} [Rain 0.0 mm; Max 23.6C; Min 9.2C; Grass 6.4C]
22nd: Overcast with good, but very hazy visibility. Pressure was 1024 mb with high 1026 mb to the S over the Channel. The cloud cleared away slowly during the morning becoming brighter with sunny spells developing. The SW'ly wind force 3 at first strengthened to force 5/6 during the afternoon raising some local dust. Visibility improved to very good and the Carneddau snow-patch could no longer be seen having completely melted on the 21st, a remarkably late date in the current climate. [Rain 0.0 mm; Max 21.4C; Min 11.2C; Grass 9.0C]
23rd: A mostly cloudy morning with some weak sunshine at times and a moderate to fresh S'ly breeze. The afternoon had a little sunshine before turning duller with the wind not moderating. Later turning brighter again with some more weak sunshine during the evening. [Rain 0.0 mm; Max 20.6C; Min 12.5C; Grass 11.3C]
24th: A cloudy start, but hints of something better to come with some breaks appearing by 09 GMT. With less wind today, there was not so much dust and tree debris flying about, the latter more noticeable because of the very dry weather. By afternoon there were sunny spells. At Beaumaris a drilling platform was stationed, work taking up to 3 weeks, to sample the sea bed around the pier. It is intended to return the pier to its former width and strengthen the timber supports. A new landing pontoon will be built and other work to enhance the kiosk and shelter. [Rain 0.0 mm; Max 20.7C; Min 14.0C; Grass 12.7C]
25th: Cloud was increasing before from 3/8 to 5/8 cover by 09 GMT. Soon mostly cloudy here although there were some blue patches to the N. In the West the sky was mostly clear and the day sunny. [Rain 0.0 mm; Max 20.5C; Min 13.2C; Grass 10.8C]
26th: A sunny morning with the temperature at 09 GMT risen to 19.8C (dewpoint 14.0C). There were a few small cumulus clouds to the S together with remnants of expanded contrails. Visibility was very good with a slight haze. The temperature went on to rise to 24.5C, the highest of the month. {Charlwood 28.6C, Hawarden 26.2C} [Rain 0.0 mm; Max 24.5C; Min 11.8 C; Grass 8.2C]
27th: The sky was almost clear at 0530 GMT then clouds developed so that at 09 GMT there were 6 oktas of cumulus and cirrus. Overnight the air temperature had not fallen below 14.6C, highest of the month. The breezy morning (S'ly force 5) soon turning dull with spots of rain at 1145 GMT on and off for about an hour. Afterwards the sky began to clear and it was a mostly sunny and dry afternoon. A clear sunny evening with less wind by 2100 GMT. [Rain trace; Max 22.0C; Min 14.6C; Grass 12.2C]
28th: A bright morning with fair-weather cumulus clouds moving along on the fresh S'ly breeze, some higher altocumulus and cirrus hinting encroachment of a frontal system. The temperature was 18.5C (dewpoint 13.2C). Pressure was 1020 mb with low 1005 N of Scotland with an associated occluded front running down the North Sea. A developing frontal-wave was W of Ireland and looked to be heading our way. It was a mostly sunny morning, but turned cloudier with a freshening f5/6 S'ly wind by noon accompanied by some spots of rain from 1230 GMT, but keeping bright with glimpses of sunshine. By 1500 GMT the low 1025 mb was over Ireland with a warm front over the Irish Sea. The cloud thickened by midafternoon with light rain setting in by 1545 GMT then heavier showery bursts during the evening as, with the low over the Isle of Man, pressure was falling. [Red Wharf Bay 40.4 mm, Pentraeth 39.7 mm, Pentraeth AWS 32.5 mm] [Rain 26.1 mm; Max 20.7C; Min 13.6C; Grass 11.8C]
29th: At midnight pressure had fallen to 1015 mb and at 0045 GMT, associated with an active cold front, there was sudden onset of heavy thunder, 'magnesium flare' white lightning and heavy rain. Thunder and lightning continued locally with very close lightning strikes and with the brilliant white light seemingly inside the house there was a series of loud fizzling discharges about 0120 GMT and the electricity supply failed. Thunder and lightning continued further away to the E until 0150 GMT. We, and a large part of SE Anglesey including Beaumaris where at the Doctor's Surgery the computer system was down and with failure of refrigeration thermally sensitive supplies could have been affected. We were without an electricity supply until 1130 GMT with a further short interruption in the afternoon. I found that electrical surges had rendered 3 electronic telephones and broadband microfilter splitters unusable, so it was out with the antique phones kept for such emergencies. TV, WiFi and equipment on Belkin surge protectors were unscathed except the line connection had failed; I had unplugged my computer system in time. I will put replacement telephones on similar protectors in future! There were reports of similar damage to electronic equipment in the area. We made coffee for breakfast by boiling water on a gas barbecue, the generator was got ready to run had the electricity supply not been restored (we were once without electricity for 48-h over Christmas during severe gales). The sky was still overcast at 09 GMT, pressure 1019 mb had risen and 26.1 mm of rain had collected in the rain gauge, the most in 24-h this very dry first 6 months of the year! Observer Charles Aron in nearby Pentraeth reported that rain during the storm was torrential and recorded 39.7 mm while Keith Ledson at Red Wharf Bay had 40.4 mm.. Slowly the morning brightened with sunny spells coming along, the afternoon was cloudier, but it was dry. [Rain 0.0 mm; Max 18.8C; Min 13.5C; Grass 13.2C]
30th: A bright morning with 6 oktas cover of mostly cirrus clouds. Pressure was 1019 mb in a transient ridge of high-pressure and the day kept fine and mostly sunny. Lines of orographic convective clouds were present through the day and cumulus persisted in the W over the Snowdonia Mountains; the mountaintops kept clear of cloud until 1900 GMT when cloud descended to 3000 ft. Later as a warm front over the Irish Sea encroached, associated with low 984 mb W of Ireland that was pushing the high-pressure over the North Sea, cloud thickened with slight rain keeping just off the W coasts of Anglesey and Llyn until after midnight. [Rain trace; Max 23.5C; Min 11.2C; Grass 7.6C]

It was the sunniest June since 1975. The 251.7 h of sunshine (142%) and [149%] recorded at RAF Valley was the 3rd highest on the Anglesey record (K&Z adjusted values). Rainfall here was 47.7 mm (75%) and [72%], lowest since 2006, brought rainfall for the first 6 months to 286.4 mm, lowest in Llansadwrn since 1929 (283.7 mm). Temperatures were above average with the mean 15.0C (+0.7) and [+1.4] of average, highest since 2006.

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