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| December 2002 monthly assessment issued 2 January
2003 |
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Monthly summaries available for: England
and Wales | Scotland | Northern
Ireland
Homogenous time series based upon selected station data:
CET | England and Wales
rainfall
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| Changeable with some cold and dry
periods then unsettled wet and very mild. |
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Diary of highlights
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1st to 4th Changeable weather with rain and
showers especially in west and north-west as areas of
low pressure and weather fronts moved south-east. It was
mainly mild, with some thunder reported on the 4th. A
gust of 61 kn was recorded at Aberdaron (Lleyn
Peninsula) on the 1st.
5th to 11th High pressure over Scandinavia
brought cold easterly winds, however it was mostly dry.
There were sunny periods at times and some patchy rain
or drizzle mainly in the south. There was some sleet or
snow in the north on the 7th, also over Dartmoor and
north-east England on the 8th. A depression over Biscay
on the 10th strengthened the easterly winds, bringing a
little snow to high ground in the West Country.
12th to 16th Dry in most places at first. A
low moving slowly north-north-east from Biscay reached
south-east England by the 15th and brought outbreaks of
rain with sleet and snow (mainly over high ground). It
was rather cold and very wet on the 14th and 15th,
patchy hill and coastal fog affected a number of areas.
17th to 19th An anticyclone centred over the
Borders migrated east-south-east to the continent
bringing cold easterly winds and some overnight frost
especially in the north. There were sunny spells later,
with some fog in northern areas. Rain reached Cornwall
and Devon later on 19th.
20th to 23rd Redesdale in Northumberland fell
to -6.6 °C early on the 20th, thereafter more unsettled
weather prevailed as Atlantic lows swept very mild moist
air across the region. Many places had a very wet 36
hours from late 20th to early 22nd causing local
flooding. Llanbedr in Gwynedd reached 15.4 °C on the
23rd.
24th to 27th Vigorous depressions from the
south-west passed close to or over the region, bringing
more rain and heavy showers. It stayed mostly very mild,
the three-day Christmas period was one of the mildest
for at least a decade. Flooding continued to be a
problem in many areas.
28th to 31st After a mainly dry start, more
very mild but very wet weather spread north-east during
the 29th and 30th as a low and its fronts stalled over
the region. Prolonged heavy rain accentuated the
flooding problems. During the 30th there were isolated
reports of thunder, while at Brighton a section of the
West Pier fell into the sea. Central London had its
wettest December on record (since 1940). Most places
began dry and cold on the 31st before further rain
spread in from the south-west.
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| Statistical details (using best available
data/estimates): updated 2003 |
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England & Wales Mean Temperature Series ( series
began in 1961 ). The final value for the month was 5.4 °C, which
is 1.1 °C above the 1961-1990 average, which is in the above average category.
England & Wales Rainfall Series ( series began
in 1961 ). The final total for the month was 128.5 mm, which is 135 % of the
1961-1990 average, which is in the above average category.
England & Wales Sunshine Series ( series began
in 1961 ). The final total for the month was 34.3 hours, which is 77 %
of the 1961-1990 average, which is in the well below average
category. Dullest since 1989, when 26.2 hours was recorded.
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| Scotland |
| Dry in the north-west, wet in the
south-east. |
| Diary of Highlights |
A dry spell from the 5th to the 20th brought a
respite from the unsettled weather experienced at the
start of December and over the Christmas period.
The changeable weather of November continued into the
first few days of December as Atlantic fronts crossed
the country. There was rain and gales in Shetland on the
1st, with a gust of 79 m.p.h. at Fair Isle. Another
front brought more rain during the night of 3rd/4th,
lingering during the day in the east.
A major change in the weather took place on 5th as a
Scandinavian anticyclone directed an east to
south-easterly airstream across Scotland for the next
two weeks. It was often cloudy, which prevented
temperatures from falling very low. However, clear skies
prevailed in the west on 11th and 12th, and more widely
from the 17th to the 19th. During the latter spell
severe frost developed, with a maximum temperature of -3
°C at Strathallan on the 19th. The following morning the
temperature had fallen to -8 °C at Dumfries and -8.6 °C
at Altnaharra.
From the 21st to the 27th, low pressure in the
mid-Atlantic pushed a series of fronts across the
country, bringing dull, mild, and often wet weather. On
the 23rd gusts reached 75 m.p.h. at Fair Isle, there was
37 mm of rain at Enochdhu, and the temperature reached
14.6 °C at Lochcarron.
During the last few days of December low pressure
remained in mid-Atlantic, but fronts travelled east over
England, leaving Scotland in a drier east-south-easterly
airstream. It was mostly cloudy, but breaks in the cloud
allowed some night frosts in the north.
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Statistical details (using
best available data/estimates): updated 2003
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Scotland Mean Temperature Series (
series began in 1961 ). The final value for the month was 3.5 °C, which
is 0.7 °C above the 1961-1990 average, which is in the above average category.
Scotland Rainfall Series ( series began in 1961
). The final total for the month was 74.8 mm, which is 48 % of the
1961-1990 average, which is in the well below average category. 3rd driest in series, driest being 1995 with 55.1 mm.
Scotland Sunshine Series ( series began in 1961
). The final total for the month was 23.2 hours, which is 78 %
of the 1961-1990 average, which is in the well below average
category.
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| Northern
Ireland |
| Dull and dry. |
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Diary of Highlights
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With the exception of some parts of County Down
the period from the 4th to 20th was fairly dry
throughout the province, while the wettest days were
recorded on the 1st, 3rd, 21st, 22nd, and 29th. Many
areas experienced nearly two thirds of the month in
which little or no sunshine was recorded, but despite
this December recorded above average durations. Across
Northern Ireland overall mean temperatures were above
normal, indeed night-time temperatures were rarely below
average.
1st to 3rd Although a mild start to the month
it was also wet and dull. Moderate and at times heavy
rain, with some locally heavy downpours occurred on the
1st and 3rd.
4th to 16th On the whole this was a fairly dry
period with some light showers occurring, producing only
slight amounts of rainfall throughout. However parts of
County Down recorded some heavier falls on the 7th, 12th
and 13th. Temperatures were around or slightly below
normal while widespread ground frosts recorded on up to
seven occasions. No sunshine was recorded on the 6th,
8th and between the 12th and 15th. In contrast the
brightest period of the month occurred between the 9th
and 11th with some areas recording over six hours of
sunshine alone on the 9th.
17th to 20th Over this period mainly dry
conditions prevailed almost everywhere. Though this was
the coldest period during the month with both day- and
night-time temperatures recording below average values.
Sunny conditions prevailed on the 17th and 18th but
little or no sunshine was recorded during the rest of
the period.
21st to 25th A mild south-westerly airflow
brought exceptionally mild conditions for this time of
the year. Bands of moderate and at times heavy rainfall
occurred throughout. The highest falls occurred over the
Mourne mountains area of County Down which recorded more
than 50 mm of rainfall over the 21st and 22nd alone.
26th to 31st Rather unsettled conditions
concluded the remainder of the month. Bands of rain and
showers tracked across the province to give some
moderate to heavy falls on the 26th, 28th and 29th.
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Statistical details (using
best available data/estimates): updated 2003
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Northern Ireland Mean Temperature Series ( series
began in 1961 ). The final value for the month was 4.9 °C, which
is 0.4 °C above the 1961-1990 average, which is in the close to average category.
Northern Ireland Rainfall Series ( series began
in 1961 ). The final total for the month was 89.6 mm, which is 82 % of the
1961-1990 average, which is in the close to average category.
Northern Ireland Sunshine Series ( series began
in 1961 ). The final total for the month was 35.8 hours, which is 102 %
of the 1961-1990 average, which is in the close to average
category.
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Homogeneous series based upon selected station data: updated
2003 |
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Central England Temperature (series begins in 1659).
The mean value for the month was 5.7 °C which is 1.0 °C above
the 1961-90 normal of 4.7 °C and is in the above average
category. Others:- 2001/3.6, 2000/5.8, 1999/5.0, 1998/5.5,
1996/2.9 °C.
England and Wales Rainfall (series begins in 1766).
The total for the month was 147.5 mm, which is 154 % of the
1961-90 average and is in the well above average category.
Others:- 2001/43.5, 2000/142.2, 1999/142.4, 1998/97.4, 1993/172.1
mm.
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| Note: Diary values are provisional based
on data available at the time. |
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