UK Lookback - April 01, 2012
One of the warmest, driest and sunniest ever
By Philip Eden
High pressure has dominated the scene for a second successive month, to such an extent that this was the fourth most anticyclonic March in 140 years of records, while February and March together topped the rankings. Mean sea-level pressure in March ranged from 11mbar above normal in Shetland to 15mbar above over northern England. There were brief unsettled spells around the 4th, 7th, and 17th, but the rest of the month was quiet and settled, and during the last ten days of the month it became unseasonably warm and remarkably sunny.
Mean maximum temperature for March ranged from 14.8°C at Southampton National Oceanographic Centre to 8.5°C at Lerwick (Shetland), while mean minimum temperature varied between 8.4°C at St Mary's (Isles of Scilly) and 0.1°C at Chesham (Bucks). Mean monthly temperature was 1.5-2.5degC above the 1981-2010 normal over most of the country, but locally in eastern Scotland it more than 3°C above. The Central England Temperature (CET) of 8.3°C was 1.7°C above the long-term mean and the highest for March for 55 years. In the entire 350-year long CET record there have been only two warmer (1938 and 1957) and one as warm (1948).
The highest maximum at a standard site (i.e excluding rooftop and mountain sites) in the UK was 23.6°C at Aboyne (Aberdeenshire) on the 27th, a new Scottish record for March, while the lowest minimum was minus 8.5°C at Braemar (Aberdeenshire) early on the 18th. The lowest daytime maximum was 3.3°C at Thorncliffe (Staffs) on the 4th, and the warmest night was that of 24th/25th with a minimum of 11.3°C at Blencathra (Cumbria).
Rainfall averaged over England and Wales during March was 30.3mm which is 43 per cent of the average for the standard reference period 1981-2010, the lowest for this month only since last year, but in the last 100 years only 14 Marches were drier while 86 were wetter. The equivalent figures for Scotland were 34mm and 44 per cent of the normal amount, and for Northern Ireland 25mm and 41 per cent. Monthly totals at routinely-available sites varied between 192mm at Cluanie Inn (Wester Ross) and just 5mm at Kinloss and Lossiemouth (both Morayshire).
Sunshine averaged over England and Wales during March was 185 hours which is 159 per cent of the 1981-2010 mean, making this the sunniest March since 1929. Indeed, in the last 100 years this was the only sunnier March, although in earlier years March 1907 was also slightly sunnier. The equivalent figures for Scotland were 139 hours and 129 per cent, and for Northern Ireland 140 hours and 120 per cent. Largest total in the UK was 213 hours at Southampton and the smallest was 70 hours at Lerwick (Shetland).
Strong winds were a rare commodity in March, as in February; the highest known gust was 57 knots at Lerwick (Shetland) on the 6th.
By Philip Eden