Llansadwrn (Anglesey) Weather Wx-Watch from the observer's notebook

The high maximum temperatures of April 2003.

Four days 14 - 17th April 2003 had a daily maximum temperature of 23C, or more. In Llansadwrn April temperatures of 20C, or more, let alone the summer months, are quite rare there being only 19 in the previous 24 years. In these terms the warmest years were 1984 with 7 days, all consecutive, from 23 -29th; and 1987 with 8 days, again 7 between 23 - 29th (what is there about these dates?), and an additional 1 on the 17th. Other years have had the odd day here 1979 (1), 1981 (1) 1993 (1), or two in 1990 (2). The 2 days of 1990 were on 1st and the 30th that was consecutive with the first 5 days of May giving a spell of 6 days. The spell of 4 days in 2003 was not only early (from the 14th) but the 25.3C, on the 16th, was highest in April on the 25-year record.

This graph shows the highest maximum in Aprils from 1979-2003. The previously highest was 24.0C in 1987 followed by 23.2C in 1990. The lowest maximum of 14.4C was recorded in 1986 while 2001 and 2002 had only 15.3C and 15.8C respectively.

Another way of looking at the same temperatures. The mean of the highest maximum in April from 1979 - 2003 is 18.7C, the 25.3C of 2003 has an anomaly of +6.6C. Other years with large positive anomalies were 1987 (+5.3), 1990 (+4.5) and 1984 (+3.7). April 1986 was cold with an anomaly of -4.3C and during the previous 9 years (1994 -2002) all have seen a negative anomaly except 1999 (+0.9).

On the 24-year record (1979 -2002) there were only 116 days in ANY month that had maximums of 25C, or more. The high of 25.3C on the 16th became the 117th and is the highest recorded on Anglesey in April. Many places including from Great Malvern to Leeds reported 26C, or more with Cardiff 26.9C the warmest. Temperatures of 25C, or more, were recorded widely from Jersey to the Isle of Skye. Temperatures in April of 25C, or more, have occurred somewhere in the UK in 27 of the past 145 years. The warmest was 29.4C recorded in London on 16 April 1949.

These pages are designed and written by Donald Perkins © 1998 - 2003 Document dated 22 April 2003 http://www.llansadwrn-wx.co.uk