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| August 2002 monthly assessment issued 2 September
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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| Warm and very thundery overall. Very
unsettled with frequent thunderstorms and localised floods at
start. Hot mid-month but some more thundery downpours in
places later. Mainly dry last week. |
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Diary of highlights
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1st to 9th With weak low pressure over or near
the region, the period was dominated by frequent
outbreaks of heavy thundery rain. Mist and fog patches
were also a regular feature first thing in country
areas. Much of northern England was very wet on the 1st,
Fylingdales (North York Moors) had 115 mm in
24 hours, their wettest day since 1984. At Leeming
(Vale of York) 91 mm fell in 24 hours, their
wettest day since 1971. From the 3rd to the 5th storms
affected a number of areas especially central England,
the south-east and East Anglia, with localised floods in
some places. During the 7th there were more localised
floods in parts of south-east England and the Midlands.
Thunderstorms deposited 60 mm in an hour at Olney
west of Bedford and at Hampstead Heath (North London),
both about 1 in 200 year events. Hampstead's total was
71 mm, with local tube networks disrupted. The 8th
and 9th saw more heavy thundery rain breaking out in
many areas.
10th to 16th Low pressure moved
away by 12th allowing a weak ridge to extend from the
Azores. It was mainly dry with good sunny periods,
however there were thundery outbreaks on the 10th and
15th over East Anglia and south-east England. Early on
the 10th Southend had 54 mm causing local flooding.
It became very warm or hot in places later. Early mist
and fog patches along with hill and coastal fog affected
some areas.
17th to 19th Mostly very warm or
hot but unsettled as more thundery rain, heavy in
places, fell in some parts. Wales and western areas were
especially wet on the 17th, while further east some
locations touched 31 °C. Most thundery activity
moved to the Midlands and East Anglia thereafter as weak
fronts migrated eastwards.
20th to 24th With
low pressure close by over the North Sea the pattern
stayed unsettled with rain at times. There were some
downpours in Kent and London late on the 20th
(25 mm in half an hour at Maidstone). The
north-east was wet on the 22nd and again on the 23rd.
Thundery showers also affected south-east and south-west
England on the 23rd. Northern England was very wet on
the 24th and thundery showers broke out later that day
over many southern counties of England. Patchy mist and
fog again visited East Anglia on many mornings.
25th to 31st Mainly dry as the Azores high
extended its influence over the region. Rather cool at
first becoming rather warm later. Thundery rain broke
out later over the extreme south on the 25th. There were
sunny periods in most parts after early mist and fog
patches cleared. A low off Northern Ireland gave
north-west districts a wet day on the 30th as it moved
away to Scandinavia.
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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 16.6 °C, which
is 1.3 °C above the 1961-1990 average, which is in the well above average category.
England & Wales Rainfall Series (series began
in 1961). The final total for the month was 67.3 mm, which is 88% 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 158.3 hours, which is 92%
of the 1961-1990 average, which is in the close to average
category.
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| Scotland |
| Spells of fine weather, punctuated by
days of rain. |
| Diary of Highlights |
After the frequent rain of mid-May to July, August
provided something of a respite, with plenty of dry and
fine weather. However, the spells of fair weather were
interrupted by occasional wet days.
The first six days of August were dominated by high
pressure, and there was a lot of warm and sunny weather.
The highest temperature recorded was 26.3 °C at
West Freugh (near Stranraer) on the 1st, but the
temperature reached 25 °C somewhere on most days.
An interruption to the fine weather occurred overnight
on 2nd/3rd, when a front moved up from England and gave
heavy rain over parts of the south and east.
A quiet spell of weather with light winds followed
from the 7th to the 10th. A front in the North Sea moved
slowly east and was replaced by a weak ridge. Slight
rain in the east cleared and was replaced by brighter
conditions in the west. A changeable westerly regime,
with showers or periods of rain, prevailed from the 11th
to the 18th. However, this included a strong rise of
pressure on the 16th that gave a fine day. As the high
retreated, warm southerly winds allowed the temperature
to reach 26.8 °C at Charterhall in the Tweed
valley.
Further fine weather with high pressure occurred from
the 19th to 26th. A break took place on the 23rd and
24th as weak fronts crossed the country. Winds were
often light northerly so that the brightest conditions
were in the south and west.
The weather became more unsettled from the 27th,
culminating on the 30th when a depression crossed the
country. This brought a wet day almost everywhere, with
35 mm of rain at Dundrennan on the Solway coast.
High pressure built from the Southwest again on the
31st.
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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 14.0 °C, which
is 1.6 °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 89.0 mm, which is 76% of the
1961-1990 average, which is in the below average category.
Scotland Sunshine Series (series began in 1961). The final total for the month was 133.8 hours, which is 99%
of the 1961-1990 average, which is in the close to average
category.
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| Northern
Ireland |
| This was the driest August month since 1995. With the
exception of the Friday 23rd the period from 15th to 28th was
fairly dry throughout the Province. Many areas experienced
around a third of the month in which little or no sunshine was
recorded, making it the dullest August month since 1999. It
was a rather warm month across Northern Ireland with overall
temperatures above normal which made it the warmest August
since 1997. Both day and night-time temperatures were rarely
below average. |
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Diary of Highlights
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1st to 9th The month started off warm, with
the warmest day occurring on the 5th. One of the highest
daily maximum temperatures of 25.7 °C was recorded in
the Castlederg area on this day. However by the 7th
conditions had become rather cool. Bands of rain brought
light to moderate rain and showers on the 2nd and 3rd
while moderate and at times heavy showers affected many
areas on the 6th and 7th. Cloudy conditions meant that
little sunshine was recorded on the 3rd, 6th, 7th and
8th.
10th to 14th Rather unsettled conditions
occurred with bands of rain and showers recorded
throughout the period. Sunny conditions prevailed on the
10th and for a time on the 13th but little or no
sunshine was recorded during the rest of the period.
15th to 18th Warm and mostly dry with some
good sunny spells. Though some light rain and scattered
showers were recorded in some areas on the 17th and
18th.
19th to 27th On the whole a
predominantly warm, sunny period. It was mainly dry in
many parts, however scattered moderate showers were
recorded on the 23rd, which were locally quite heavy in
northern and central areas of province.
28th to
31st Scattered showers on the 28th followed by
moderate to heavy rainfall on the 29th gave rise to
daily rainfall totals of 12 mm or more in some
places. It was fairly dry for the remainder of the
month, but dull.
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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 14.9 °C, which
is 1.1 °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 57.2 mm, which is 60 % 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 128.4 hours, which is 95 %
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
17.0 °C which is 1.2 °C above the 1961-90
normal of 15.8 °C and is in the above average category.
Others:- 2001/16.8, 2000/16.6, 1999/16.1, 1998/15.9,
1997/18.9 °C.
England and Wales Rainfall (series begins in 1766). The total for the month was 75.8 mm, which
is 98 % of the 1961-90 average and is in the close to average category. Others:- 2001/86.3, 2000/65.9, 1999/116.6, 1998/48.7,
1997/98.9 mm.
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| Note: Diary values are provisional based
on data available at the time. |
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