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| January 2001 monthly assessment issued
1/2/2001 |
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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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| A very sunny month with temperatures
and rainfall near average. A wet and mild start, mainly dry
for a fortnight, then colder with a little snow. The fourth
week began mild wet and windy but frost and fog returned at
month's end. |
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Diary of highlights
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1st - 4th January began mild and wet as low
pressure edged eastwards. Outbreaks of rain and showers
were heavy at times particularly in the west.
5th
- 11th A complex low-pressure area over the region
migrated to southern Scandinavia by 9th. There were
scattered showers, some wintry, especially in northern
and western areas, however southeast parts were often
dry and mainly sunny. High pressure near Iceland then
moved to central Scotland by 10th and 11th producing
strong and cold east or north-east winds over southern
England.
12th - 20th The high pressure then slowly receded east
to Leningrad by 18th. The weather was mostly dry and sunny
at first under the high pressure, but much colder from the
16th onwards with frost and fog at night. The fog was slow
to clear at times in the morning. During the 18th to the
20th weak low pressure systems affected the region with
snow falling in places. Some snow flurries were experienced
in southern counties during the 18th, while a few centimetres
of snow carpeted East Anglia on the 19th and also in places
in north-east England. Redesdale (Northumberland) and Redhill
(Surrey) recorded -8.0 °C early on the 19th and 20th.
21st - 25th With
low pressure to the west and north-west, a very mild,
wet and windy period ensued, preceded by some snow in
central and northern areas. Sunny periods alternated
with bands of rain and showers, some of which were heavy
and accompanied by thunder especially in the west and
north. A gust of 63 kn was recorded at Llanbedr
(Gwynedd) on the 23rd.
26th - 31st After a
wet start with outbreaks of rain, sleet and snow the
27th, 28th and 29th were mainly sunny and dry with some
fog and frost at night. An occluded front became stalled
over England and Wales during the last two days.
Although mild in the south-west most places were rather
cold with overnight frost, patchy fog and outbreaks of
light rain and drizzle.
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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 3.2 °C,
which is 0.2 °C below the 1961-1990 average, which
is in the close to average category.
England & Wales Rainfall Series (series began
in 1961). The final total for the month was 74.2 mm,
which is 82 % of the 1961-1990 average, which is in
the close to average category.
England & Wales Sunshine Series (series began
in 1961). The final total for the month was 74.5 hours,
which is 153 % of the 1961-1990 average, which is in
the exceptionally above average category. Sunniest in
series, previous sunniest 1991 with 66.3 hours.
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| Scotland |
| Dry and sunny, especially in the
north. |
| Diary of Highlights |
January was a quiet month for weather and was notable
for a long anticyclonic spell in mid-month with light
southerly winds, hard frosts and sunny days. This
contributed to record sunshine totals being reached at
many northern stations. It is the third time in the last
four months that places in the north of Scotland have
broken sunshine records.
The first week was dominated by low pressure to the
north, but the main belt of disturbed weather lay well
to the south and most of the rain was showery.
The long anticyclonic spell began on the 9th and lasted
until the 20th, during which time the main centre of high
pressure transferred from northwest of Scotland to Russia.
The wind direction was mostly from the south, and this
prevented cloud from the North Sea from invading the country.
The weather was often sunny by day and frosty by night,
with the temperature at Aviemore falling to -13 °C
on the 17th.
The last 10 days of the month returned to the
cyclonic theme, and was heralded by snow on the 21st as
Atlantic fronts encountered the cold continental air. As
in the first week, the cyclonic spell was associated
with light winds and showers rather than prolonged
periods of rain.
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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 1.4 °C,
which is 0.7 °C below the 1961-1990 average, which
is in the below average category. Coldest since 1987
when 0.6 °C was recorded.
Scotland Rainfall Series (series began in 1961).
The final total for the month was 91.1 mm, which is
59 % of the 1961-1990 average, which is in the well
below average category.
Scotland Sunshine Series (series began in 1961).
The final total for the month was 52.4 hours, which is 150 %
of the 1961-1990 average, which is in the exceptionally
above average category. Sunniest in series, previous
sunniest 1963 with 50.9 hours.
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| Northern
Ireland |
| This was another dry January month. |
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Diary of Highlights
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The period 20th to 25th was wettest and mildest overall,
but the two-week period up to 20th was dominated by cold,
dry weather. All areas experienced around 10 to 12 quite
sunny days, which lifted sunshine totals to well above
average across all areas. Temperatures only reached or
exceeded 10 °C locally on the 1st and 23rd, otherwise
daytime maximum temperatures were typically between 3 °C
and 7 °C. Overnight temperatures as low as -6 °C
to -8 °C were recorded frequently across some central
and western areas between the 14th and 19th.
1st - 7th Generally unsettled with spells
of rain or showers, but rainfall amounts mostly small.
Mild at first, but turning colder from the 2nd/3rd.
8th - 20th Dry and cold, with widespread
moderate, locally severe frosts. Very sunny from the 8th
to 14th inclusive, then generally cloudy.
21st - 31st Unsettled, mild and quite
wet till the 25th. Then drier and colder with another
cold, sunny spell from 26th to 29th. Mild and unsettled
again on the 30th and 31st, but with only small amounts
of rainfall.
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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 3.1 °C, which
is 0.6 °C below the 1961-1990 average, which is
in the below average category. Coldest since 1991 when
2.9 °C was recorded.
Northern Ireland Rainfall Series (series began in
1961).
The final total for the month was 65.3 mm, which is
56 % of the 1961-1990 average, which is in the well
below average category.
Northern Ireland Sunshine Series (series began in
1961).
The final total for the month was 66.6 hours, which is 153 %
of the 1961-1990 average, which is in the exceptionally
above average category. Sunniest in series, previous
sunniest 1961 with 59.9 hours.
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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 3.2 °C which is 0.6 °C
below the 1961-90 normal of 3.8 °C and is in the below
average category.
Others:- 2000/4.9, 1999/5.5, 1998/5.2, 1997/2.5 °C.
England and Wales Rainfall (series begins in 1766).
The total for the month was 84.4 mm, which is 93 %
of the 1961-90 average and is in the close to average category.
Others:- 2000/46.4, 1999/128.6, 1998/120.4, 1997/16.5 mm.
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| Note: Diary values are provisional based
on data available at the time. |
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