By Philip Eden

Low pressure dominated Britain's weather during the first five days and again from the 21st onwards, but from the 6th-20th high pressure over Scandinavia or close to the British Isles was the controlling factor.

The Central England Temperature (CET) for December 2002 was 5.7°C, which is 0.6 degC above the mean for the standard reference period 1971-2000 and the highest only since 2000; in the last 100 years 76 Decembers were colder as measured by the CET, four had the same mean temperature, and 20 were warmer (including 1994, 1997 and 2000 in recent years).

Daytime temperatures were slightly below normal in most parts of the UK (about 1.5 degC below in Northern Ireland), but nights were warmer than average everywhere and in parts of southeast England night-time temperatures were as much as 3 degC above normal.

The warmest weather over England and Wales occurred on the 23rd and 24th, with 15.4°C on the 23rd at Llanbedr in northwest Wales and 15°C on the 24th at Torquay in Devon. Frosty nights were rare in southern England, but there were some severe frosts mid-month in Scotland and Northern Ireland, and the lowest reading of the entire month was -8.4°C at Altnaharra in Sutherland, early on the 17th.

Rainfall, averaged over England and Wales, was 144mm which is 52 per cent above the average for the standard reference period 1971-2000. During the last 100 years, only 12 Decembers were wetter (most recently in 1993) while 88 were drier. In the main population centres in Scotland the total for December 2002 was 72mm which is 3 per cent below the normal amount, whereas the Northern Ireland total of 67mm was 20 per cent below.

Twice the normal rainfall was exceeded over much of Sussex, Surrey, Kent and Greater London (2.6 times in central London), and also at a few sites in the north Midlands and Yorkshire. By contrast, it was an exceptionally dry month over much of northern Scotland, and several sites in the northwest highlands recorded less than 15 per cent of their normal amount of rain.

Sunshine over England and Wales totalled 34 hours during December 2002, almost 30 per cent below the long-term average for the month, and the lowest since 1989. The equivalent figure for Scotland's main population centres was 27 hours (also 30 per cent below), but for Northern Ireland it was 40 hours (just two per cent below). Monthly aggregates ranged from 57 hours at RAF Valley, Anglesey, to just 9 hours at Fair Isle (between Orkney and Shetland).

(c) Philip Eden