The UK in December
Mike Hulme on last month’s weather
DAYTIME TEMPERATURES
December was clearly a month
of two contrasting halves - the first two weeks being extremely mild with
daytime temperatures up to 4C above average and the last two weeks seeing temperatures
fall by up to 10C. The month as a whole
remained milder than is average for December, more so in the south and east
than in the north and west. The last
week of the year was the coldest in the UK since January 1997 and in some
regions the coldest since 1987. The
final estimate for the year 2000 was that the UK was about 0.5C above the
long-term average - only 1993 and 1996 have been cooler than this average
during the last decade. The decade as a
whole has been about 0.6C warmer than the 1961-90 normal.
RAINFALL
Although temperatures fell
as December progressed, for the most part the rainfall continued, although in
the week after Christmas this turned to snow for most regions. This was the fourth consecutive month with
exceptionally high rainfall totals in the UK, December averaging about 60%
above the normal, quite similar to December 1999. The west country was the most anomalous with well over two times
the December average being recorded. In
contrast, Skegness and Lerwick in the east and north were a few millimetres
drier than usual. The wettest day of
the month, and second wettest of the year, was the 8th with a
nationwide average of 15mm falling.
SUNSHINE
The interesting trend of
very wet, but sunny, months in the UK continued. Following October and November, December 2000 was also about 9%
sunnier than average across the country.
This was due mainly to higher sunshine totals in the south, east and
north - locations in the west like Anglesey and Belfast barely managed an hour
of sunshine per day, 25% or more below the normal. The sunniest day for about 2 months occurred on the 30th
December with a nationwide average of 4.7 hours of sunshine. Six of the last seven Decembers have been
sunnier than average, only 1997 interrupting the sequence.
Dr Mike Hulme is a Director
of the Tyndall Centre for Climate Change Research, at UEA
(more details at website at
www.tyndall.uea.ac.uk)
December 2000: Very wet, mild at first
Daytime Temperature: 0.6C above average; Rainfall: 63% above average; Sunshine: 9% above average.
[all average figures are
based on the 1951-80 average]
Mean monthly extremes:
Warmest Guernsey 11.3C
Sunniest Folkestone 69 hours sun
Wettest Eskdalemuir 328mm
Coldest Lerwick 6.4C
Cloudiest Lerwick 19 hours sun
Driest Skegness 53mm