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| April 2000 Monthly Assessment issued
2/5/2000 |
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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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| Very wet with record breaking
rainfall as a succession of rain bands and thundery showers
affected the region. A cold first half with overnight frosts
and some snow at times. Mostly rather warm or warm the latter
half. |
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Diary of highlights
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1st – 4th A cold wet start to the month
with heavy bursts of rain in many places. The rain turned
to snow over the Pennines, Welsh mountains, Dartmoor and
Exmoor during the 3rd and also on low ground at times later.
Between 4 and 8 cm of snow was lying over much of the high
ground away from the south-east and East Anglia early on
the 4th. London had its coldest April day for 34 years with
a maximum temperature of 4.2 °C.
5th – 10th High pressure became established over
the region giving dry conditions almost everywhere but with
some overnight frost. It was generally sunny after the clearance
of early morning mist or fog patches and became very warm
in many parts on the 8th (London reached 17.6 °C). Occasional
light rain affected areas near the North Sea during the
8th - 9th.
11th – 15th Cold and often very wet and unsettled
weather prevailed as low pressure positioned itself over
the region. Outbreaks of rain heavy at times with hail and
thunder occurred, particularly on the 12th/13th, although
there were sunny spells in between. Some snow fell over
high ground on the 12th and there was overnight frost in
many places.
16th – 26th With depressions passing over or close
by to the west the very wet theme continued. However the
mainly southerly winds allowed rather warm or warm temperatures
to be registered after the 18th. Bands of rain or showers,
often prolonged and heavy, continued to affect many areas.
Thunder and hail accompanied some showers, and on the 23rd
funnel clouds were reported from Suffolk. Most days however
saw sunny periods.
27th – 30th Apart from a wet day on the 28th (especially
the south-east and East Anglia) most parts had long sunny
spells with warm or very warm temperatures. At Barbourne
(Worcester) and Nantmor (Gwynedd) 21.0 °C was reached on
the 30th, although places adjacent to the North Sea stayed
cooler, with rain affecting some areas in the extreme south-east
and East Anglia.
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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 value for the month was 7.5 °C, which
is 0.2 °C above the 1961-1990 average, which is in the close
to average category.
England & Wales Rainfall Series ( series began
in 1961 ). The total for the month was 132.5 mm, which is
221 % of the 1961-1990 average, which is in the exceptionally
above average category. Wettest in series, previous wettest
1998 with 121.8 mm.
England & Wales Sunshine Series ( series began
in 1961 ). The total for the month was 137.8 hours, which
is 96 % of the 1961-1990 average, which is in the close
to average category.
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| Scotland |
| Heavy rain lashes the north-east. |
| Diary of Highlights |
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Very wet weather accompanied by strong NE
winds brought floods to the north-east from the 24th to
the 26th. Monthly rainfall totals in Kinloss, Aberdeen and
Edinburgh were about 130 mm. This is very unusual for April,
but wetter conditions have been experienced at other times
of the year. For instance, Aberdeen recorded 252 mm in November
1997 and Kinloss amassed 299 mm in September 1995. Earlier
in the month, an anticyclone brought dry and sunny weather
from the 4th to the 6th. This followed another north-easterly
outbreak which brought heavy snow to the higher parts of
Grampian Region. In fact, the first half of April was characterised
by bursts of cold NE winds separated by more settled spells.
A showery theme with variable or southerly winds blowing
around a low to the west of Ireland dominated the week or
so leading up to the main north-easterly onslaught. Following
this, the weather settled down, with winds remaining from
an easterly point.
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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 value for the month was 5.3
°C, which is 0.1 °C below the 1961-1990 average, which is
in the close to average category.
Scotland Rainfall Series ( series began in 1961
). The total for the month was 100.1 mm, which is 124 %
of the 1961-1990 average, which is in the above average
category.
Scotland Sunshine Series ( series began in 1961
). The total for the month was 131.6 hours, which is 96
% of the 1961-1990 average, which is in the close to average
category.
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| Northern
Ireland |
| A cool, wet month. |
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Diary of Highlights
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More than half the month's rainfall was due
to five very wet days, whereas the weather was often dry
and sunny during the first three weeks. Widespread overnight
frosts were recorded during this time however, with lowest
temperatures down to -5 °C being among the lowest air temperatures
recorded in Northern Ireland since January 1999. The 25th
to 27th were dull, very wet and cold. Rainfall amounts over
the three days typically ranged between 30 and 50 mm, with
persistent rain recorded for 50 hours or more across many
areas.
1st - 2nd Dull, cold and wet across all areas.
3rd - 9th Dry and very sunny but with widespread
overnight frosts.
10th – 15th Persistent rain on the 10th was followed
by cold, showery weather on the 11th and 12th. The period
13th to 15th was largely dry, but it remained rather cold
and with a widespread sharp frost overnight on the 14th/15th.
16th & 17th The extreme east enjoyed a dry, sunny
afternoon and evening on Sunday, otherwise it was dull,
cold and wet.
18th – 24th A mixture of showers and sunshine and
less cold.
25th – 27th Dull, cold and very wet.
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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 value for the month was 6.4 °C, which
is 0.6 °C below the 1961-1990 average, which is in the below
average category. Coldest since 1989, when 5.7 °C was
recorded.
Northern Ireland Rainfall Series ( series began
in 1961 ). The total for the month was 102.1 mm, which is
154 % of the 1961-1990 average, which is in the well above
average category.
Northern Ireland Sunshine Series ( series began
in 1961 ). The total for the month was 134.5 hours, which
is 92 % 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 7.8 °C which is 0.1 °C
below the 1961-90 normal of 7.9 °C and is in the close to
averagel category. Others: 1999/9.4, 1998/7.7, 1989/6.6
°C.
England and Wales Rainfall (series begins in 1766).
The total for the month was 142.6 mm, which is 230 % of
the 1961-90 average and is in the exceptionally above average
category. Others:- 1999/75.8, 1998/130.9 mm.
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| Note: Diary values are provisional based
on data available at the time. |
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