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| September 2002 monthly assessment issued 1 October
2002 |
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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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| Dry and rather warm overall. Dry and
sunny at first. Very wet at start of second week with
torrential rain in places. Mainly rather warm, dry and
anticyclonic. |
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Diary of highlights |
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1st to 4th A mainly dry and sunny start as
high pressure drifted east to Russia, with a low forming
over the North Sea by the 4th. It was generally rather
warm with patchy mist and fog in places at first but
there were outbreaks of rain in the south-west later.
5th to 9th Changeable to begin with as low
pressure south of Iceland moved to the Irish Sea by the
7th. There were occasional outbreaks of rain and
showers, especially in the west and north-west. Some
heavy thundery rain affected Kent and Sussex overnight
6th/7th. A depression from Biscay on the 8th passed over
the region during the 9th , bringing squally winds and
depositing copious amounts of rain over a wide area. The
rain was torrential in places causing flooding,
especially in the north-west Midlands and the Swanage
area - where 121 mm fell in 24-hrs, a one in 280-year
event. Parts of the Isle of Wight were also deluged with
up to 75 mm of rain in 24-hours.
10th to 20th
Mostly dry under the influence of a ridge of high
pressure stretching from an anticyclone over
Scandinavia. The high centre later migrated to a
position north then north-west of the UK. It was rather
cloudy at times in eastern areas but there were often
good sunny periods in central and western parts. Rather
cool at times near the east coast but mostly rather warm
or warm at times in remaining areas with Exeter reaching
26.5 °C on the 13th. Occasional spots of rain broke out
over east coast counties and East Anglia from the 16th
onwards. Some thundery rain affected south-west England
at times during the 19th and 20th.
21st to
30th The high pressure continued to dominate the
weather, later drifting south then eastwards into the
continent. Though mainly dry with lengthy sunny spells
there were some scattered light showers in places on the
22nd, and in the east on the 23rd and 24th as weak
fronts gyrated round the high. Some showery rain also
affected northern and eastern areas early on the 26th
with thunder reported in East Anglia. Temperatures were
mostly near normal, becoming rather warm at times
especially after the 28th as a south-east airflow became
established. The chillier night time spots had patchy
mist and fog in the morning, with some districts having
thick fog for a few hours. Some places experienced their
first ground frosts of autumn. The last day saw showery
outbreaks over Wales and south-west England, with a
report of thunder in
Cornwall. |
| 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 13.9 °C, which
is 0.8 °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 34.8 mm, which is 45 % of the
1961-1990 average, which is in the well below average category.
England & Wales Sunshine Series ( series began
in 1961 ). The final total for the month was 154.6 hours, which is 117 %
of the 1961-1990 average, which is in the above average
category.
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| Scotland |
| Anticyclonic and very dry. |
| Diary of Highlights |
The weather of September was dominated by
anticyclones and hence was very dry. There was an
unsettled spell from the 4th to the 10th, and this
included one very wet day (the 9th). Apart from this,
rainfall was scarce, although it was not always sunny.
September started with an anticyclone over England
that moved steadily east to reach Denmark by the 3rd.
Fronts pushed cloud south across Scotland on the 1st,
but retreated north the next day. The bulk of Scotland
experienced three fine days, with the temperature
reaching 24.7 °C at Fyvie Castle in Aberdeenshire on the
2nd.
A steady fall of pressure introduced an unsettled
spell from the 4th to the 10th as a depression moved
south from Iceland to the English Channel. The weather
was mostly showery, but the showers were heavy with
flooding in Inverness on the 8th. The next day a front
returned from the east to give a wet day, with 42.6 mm
at West Freugh near Stranraer.
From the 11th to the 15th a large anticyclone over
Scandinavia moved slowly southwest towards the Northern
Isles. This gave a spell of warm and sunny weather to
most parts, with the temperature reaching 25.6 °C at
Lochcarron on the 12th.
The anticyclone became slow moving to the west of
Scotland between the 15th and 20th. The change in the
position of the High introduced cloud to many parts,
with drizzle in the far north.
Colder, clearer air spread from the north on the
21st, with the anticyclone settling close to Scotland
until the 24th. This brought a series of sunny days, but
with cold nights. At Tulloch Bridge, the temperature
fell to -2.5 °C on the 23rd and 24th.
Weak fronts crossed the country from the north and
west on 25th and 26th, bringing cloud and some rain.
High pressure became re-established on 27th and 28th,
but the air was mild and rather cloudy. Southwesterly
winds and weak fronts returned by the end of the month,
but it remained warm with only a little 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 11.8 °C, which
is 1.3 °C above the 1961-1990 average, which is in the well above average category.
Scotland Rainfall Series ( series began in 1961
). The final total for the month was 51.7 mm, which is 36 % of the
1961-1990 average, which is in the well below average category. 2nd driest in series, driest being 1972 with 31.6 mm.
Scotland Sunshine Series ( series began in 1961
). The final total for the month was 110.2 hours, which is 112 %
of the 1961-1990 average, which is in the above average
category.
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| Northern
Ireland |
| Warm, Dry and Sunny This was the driest September month
since 1996. The majority of Septembers' rainfall was recorded
during the first 10 days and last day of the month. The period
from 11th to 29th was fairly dry throughout the Province,
however some western areas recorded some isolated and locally
quite heavy showers on the 29th. It has been the sunniest
September since 1997. |
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Diary of Highlights |
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1st to 4th This was a rather warm and sunny
period across the province. It was mainly dry though
some scattered light showers occurred locally on the 3rd
and 4th, however accumulations recorded would have been
no more than one or two millimetres.
5th to
10th Low pressure prevailed bring rather unsettled
conditions. Atlantic depressions and their associated
weather fronts brought bands of rain and showers. Some
heavy downpours occurred locally with between half an
inch and an inch of rainfall being recorded on a number
of occasions. Long sunny spells were recorded throughout
the period.
11th to 14th High pressure
dominated much of the weather during this period. It was
warm and dry with some good sunny spells, except on the
12th, which was quite dull. One of the highest
temperatures for the month was 21.8 °C which was
recorded on the 11th in the Armagh area. Many areas also
recorded maximum day-time temperatures of 20 °C on the
13th and 14th some 4 °C above the month average.
15th to 25th A dry settled period with little
or no measurable rainfall measured anywhere. Daytime
temperatures remained on the whole a degree or two above
the average. Many areas recorded night-time temperatures
in double figures between 15th and 19th. Slight ground
frosts were recorded on up to four occasions in northern
coastal areas while elsewhere they occurred locally on
the 23rd and 24th. The dullest period of the month
across Northern Ireland occurred between the 15th and
19th when virtually no sunshine was recorded anywhere
apart from around one hour of sunshine on the 16th.
26th to 30th Early morning fog formed on the
26th and 27th which was locally dense in places.
Temperatures were around or slightly above normal
initially, though it became rather warm on the 29th,
reaching 19 °C by the 30th in many locations. Between
the 26th and 28th it was mainly dull, though some sunny
spells were recorded on the 29th and 30th. Isolated
light showers occurred on the 29th though these were
locally quite heavy in the west of the province. The
month of September ended with a band of moderate to
heavy rain moving across the country from the south-west
during the evening and late night of the 30th. |
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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 12.8 °C, which
is 0.9 °C above the 1961-1990 average, which is in the above average category.
Northern Ireland Rainfall Series ( series began
in 1961 ). The final total for the month was 42.3 mm, which is 42 % 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 124.1 hours, which is 115 %
of the 1961-1990 average, which is in the above 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 14.4
°C which is 0.8 °C above the 1961-90 normal of 13.6 °C
and is in the above average category. Others:- 2001/13.4,
2000/14.7, 1999/15.6, 1998/14.9, 1997/14.2 °C.
England and Wales Rainfall (series begins in 1766). The total for the month was 40.8 mm, which is 52
% of the 1961-90 average and is in the well below average category.
Others:- 2001/82.9, 2000/132.6, 1999/124.9, 1998/104.4,
1997/30.8 mm. |
| Note: Diary values are provisional based
on data available at the time. |
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