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| July 2002 monthly assessment issued 1 August
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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| Unsettled and chilly first half
followed by a warm dry spell, then more changeable. Hot and
thundery later with some downpours and local flooding. Fresher
closing days. |
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Diary of highlights
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1st - 12th Unsettled and cool with frequent
outbreaks of rain as low-pressure systems and their
associated fronts traversed the region. Most days were
decidedly wet especially in central and southern areas
of England. The rain was often heavy and accompanied by
thunder, the latter being reported on the 2nd, 3rd and
5th. Thundery showers also affected a number of places
on the 10th to 12th.
13th - 18th A ridge of
high pressure extended from the Azores most of the time,
bringing mainly dry weather, good sunny periods and very
warm conditions at times, especially in the south. There
was occasional light rain or showery outbreaks in
south-west England on the 13th and in northern parts
during the 15th to 17th as weak fronts grazed the area.
North-east England had some heavier showers on the 18th.
19th - 25th More changeable during this
period with southern areas staying mainly dry apart from
the odd outbreak of light rain or drizzle. A small
active low crossed central Britain on the 19th - 20th
bringing heavy rain at times to the Midlands and
northern areas. At Sutton Bonington, Notts, 25 mm
fell in 2 hours overnight. A severe hailstorm was
observed at Santon Downham on the 20th , while East
Anglia, Lincolnshire and east Kent had thundery showers
later. Some hill and coastal fog affected south-western
parts during the 25th.
26th - 31st After the
sun dispersed some early patchy mist or fog, it became
very warm or hot for most of the period. Herne Bay in
Kent reached 32°C on the 28th, while in East Anglia
thunderstorms broke out later, rumbling on into the next
morning. On the 29th 33°C was touched at Northolt in
Middlesex and 32°C in central London making it the
hottest July day in the capital since 1989.
Afternoon/evening storms mostly north-west of London
drifted towards the Wash overnight. The 30th saw heavy
thunderstorms break out widely over the Midlands,
northern England, East Anglia and parts of south-east
England giving torrential downpours and local flooding
in places. Kirklees, West Yorkshire received nearly
50 mm in 4 hours, while Marham in Norfolk caught
83 mm in about 18 hours from two storms ending at
7 a.m. the next morning. The 31st saw early morning
storms in Norfolk petering out but more thundery rain
with local downpours developed over central southern
England during the day, Bicester, Oxon catching
52 mm. Heavy rain arrived in south-west England
later.
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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 15.4°C, which
is 0.0 °C above 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 83.3 mm, which is 134 % of the
1961-1990 average, which is in the above average category.
Wettest since 1988, when 127.5 mm was recorded.
England & Wales Sunshine Series ( series began
in 1961 ). The final total for the month was 164.0 hours, which is 90 %
of the 1961-1990 average, which is in the below average
category.
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| Scotland |
| Very wet end to an unsettled
month. |
| Diary of Highlights |
The unsettled south-westerly regime that had
prevailed since mid-May continued until mid-July, giving
mostly showery weather. Thereafter a rise in pressure
led to a decrease in rainfall amounts, but there were
large amounts of cloud. During the last five days,
slow-moving fronts brought heavy rain to most
districts.
The first 12 days of July were unsettled, with low
pressure close to Scotland. However, winds were light,
the rain came mostly in showers, and the sun shone
between the showers.
From the 13th to the 26th there was a change in
weather type as a rise in pressure took place,
culminating on the 18th when an anticyclone was centred
over Scotland. It was much drier than before, but weak
fronts and humid airmasses ensured that it was mostly
cloudy. Thus a continuing theme of the summer was the
rarity of dry and sunny days.
During the last five days of July a front marking the
boundary between hot air over England and fresher
weather to the north and west became slow moving over
Scotland. Heavy rain arrived in the north-west on the
27th, but the wettest day was the 30th, when there were
many reports of flooding. Fife Ness received
59.4 mm of rain, and Leuchars and Kinloss
experienced their wettest July day on
record.
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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 12.6 °C, which
is 0.0 °C above the 1961-1990 average, which is in the close to average category.
Scotland Rainfall Series ( series began in 1961
). The final total for the month was 126.3 mm, which is 132 % of the
1961-1990 average, which is in the above average category.
Scotland Sunshine Series ( series began in 1961
). The final total for the month was 100.8 hours, which is 71 %
of the 1961-1990 average, which is in the well below average
category. 3rd dullest in series, dullest being 1961 with 99.5 hours. Also dullest since 1970, when 100.7 hours was recorded.
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| Northern
Ireland |
| Wet and dull. Unsettled conditions made this a wet and dull
July in all areas of the province. Conditions by day were also
cool, with daily maximum temperatures below normal in all
areas, however by night minimum temperatures proved mild. |
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Diary of Highlights
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1st to 4th Unsettled and cool. Bands of often
heavy rain and showers gave daily rainfall totals in
double figures in some locations on the 1st and 4th,
however little or no precipitation and plentiful
sunshine was recorded across the province on the 3rd.
The 1st proved one of the coolest days of the month,
with daily maximum temperatures struggling to exceed
14°C in many locations.
5th to 12th Sunny conditions gave daily
maximum temperatures slightly above average on the 5th,
however below-normal temperatures then returned and
persisted from the 6th to the 12th. Unsettled conditions
again dominated, with frequent showers interspersed by
good spells of sunshine. Thunderstorms and heavy spells
of showery rain led to flooding problems in some
locations on the 12th.
13th to 17th Largely dry with only isolated
showers recorded during this period. Warm and sunny
conditions dominated on the 13th and 14th, with
temperatures reaching highs of around 22°C in places on
the 14th. Cloudier conditions with only brief spells of
sunshine returned on the 15th, 16th and 17th, causing
temperatures to fall to values close to or slightly
below average for the time of the year.
18th to 22nd Unsettled with bands of rain
followed by scattered showers and sunny spells. A slight
ground frost was recorded in isolated locations on the
18th, while by day maximum temperatures fell below
average on the 19th and 20th. The 20th also proved
largely dry and sunny across the province.
23rd to 27th Largely dry with only scattered
showers recorded across the province on the 23rd, 24th
and 27th. Above average temperatures were recorded on
the 25th and 27th, with values reaching highs of around
23°C in many locations on the 27th, making this the
warmest day of the month in most parts. Conditions were
however quite cloudy with only brief spells of sunshine
recorded on each of the dates during this spell.
29th to 31st Unsettled and dull with spells of
often heavy and thundery rain leading to flooding
problems in many parts during the morning of the 30th.
By day temperatures fell below average, however by night
conditions proved very mild, with values well above
normal for the time of
year.
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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 13.6 °C, which
is 0.4 °C below 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 104.7 mm, which is 147 % of the
1961-1990 average, which is in the well above average category.
Northern Ireland Sunshine Series ( series began
in 1961 ). The final total for the month was 104.9 hours, which is 75 %
of the 1961-1990 average, which is in the well below 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 16.0 °C
which is 0.1°C below the 1961-90 normal of 16.1°C and is
in the close to averagel category. Others:- 2001/17.2,
2000/15.5, 1999/17.7°C.
England and Wales Rainfall (series begins in 1766). The total for the month was 93.2 mm, which
is 150 % of the 1961-90 average and is in the well above average
category. Others: - 2001/73.2, 2000/63.8, 1999/26.3, 1998/54.4,
1997/53.5, 1993/88.7, 1992/89.7, 1988/139.0 mm.
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| Note: Diary values are provisional based
on data available at the time. |
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