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| April 2006 monthly assessment
issued 3 May 2006. |
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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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| It was quite a changeable
month with Atlantic depressions crossing the north of the
UK and sinking south-east across the North Sea bringing
some unsettled spells of weather with rain, sleet and at
times hail and snow. This unsettled weather was interspersed
with more benign periods, under the influence of high-pressure
ridges. The mean rainfall total for the month was below
average but with a range from close to normal across north
Wales and north-west England to significantly below normal
in parts of the south-west. There were some colder spells,
hence the snow, but this was offset by some warm periods,
which brought temperatures above normal overall. |
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Diary of highlights
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1st and 2nd: April started on an unsettled note.
Initially there was low pressure to the north-west of
Ireland. Weather fronts and troughs, associated with
this low, swept eastward across England and Wales with
the rain enhanced across southern districts overnight
into the 2nd as a frontal wave ran eastwards. During
the 2nd the low centre meandered eastwards across northern
England maintaining showery conditions, with some of
the showers heavy and thundery. Despite the rain and
showers it was locally warm or rather warm with Margate
(Kent) reaching 16.1 °C on the 1st and Pershore
(Worcestershire) 14.7 °C on the 2nd.
3rd and 4th: Overnight into the 3rd the low
drifted eastwards into the North Sea. As a result a
northerly flow developed with this enhanced further
by a build of pressure to the west of the UK. Showers
developed and drifted southwards in this flow with some
of the showers heavy and of hail, sleet and locally
snow. Northern and eastern parts of England bore the
brunt of these showers with many southern and western
areas remaining dry and sunny (Weymouth 11.5 hours on
the 3rd and Anglesey 11.6 hrs on the 4th). Another consequence
of the northerly flow was to introduce cooler conditions
with particularly northern and eastern parts rather
cold.
5th: A ridge of high pressure built from the
west leaving most with dry and fairly sunny conditions.
Both Woburn (Bedfordshire) and Fishguard (Pembrokeshire)
recorded 12.5 hours of sunshine. Despite the sunshine
temperatures were only around normal. It was also a
frosty start in rural parts with both Sennybridge (Powys)
and Shap Fell recording minima of -5.7 °C. It became
frosty again is some country areas on the night of the
5th with Benson (Oxfordshire) falling to -4.5 °C.
6th to 9th: The ridge of high-pressure gave way
early on the 6th, allowing a weather front to sink south.
A more unsettled period of weather followed with low
pressure dominating. The low, initially to the north
of the UK, drifted south-east with showers feeding across
the county. As the low drifted across the North Sea
and the flow became northerly the showers turned increasingly
wintry. Large hail was reported in Manchester on the
7th while heavy snow showers on the 8th resulted in
the Premiership football match at Sunderland being abandoned.
There were further wintry showers on the 9th, mainly
in the north and east. Heavy snow showers resulted in
the closure of the M62 for a few hours and there was
a covering of snow in other parts. Showers became more
active across south-east England during the early hours
of the 10th and locally intense, with 15 cm of snow
reported from Tunbridge Wells.
10th to 15th: As the low drifted away a ridge
of high pressure built across England and Wales. However,
this was only a transient feature, soon supplanted by
an active weather system which brought rain then showers
across all areas on the 11th. The rain/showers were
heavy in places with Capel Curig (Gwynedd) recording
42.8 mm (1.69 inches) in the 24 hours ending at 1800
on the 11th. There were also reports of thunder. Further
frontal systems pushed across from the west on the 12th
and 13th bringing rain accompanied by strong winds.
Capel Curig (Gwynedd) recorded a gust of 51 knots on
the 13th. Despite the breeze and spells of rain, it
was locally warm with Margate (Kent) reaching 17 °C
on the 13th. A weak, slow-moving weather front straddled
southern counties on the 14th leaving many other parts
dry and fairly sunny. Indeed Cromer recorded 12.7 hours
of sunshine. It was cloudier on the 15th with some rain
in the south but Preston Town Hall reached 17.1 °C.
16th to 21st: Slow moving weather fronts and
showers affected northern parts through this period
while amounts of rain in the south were small. There
was also some warm, hazy sunshine in places with Eastbourne
recording 12.5 hours on the 18th. On the 21st, showery
rain across north-east England pushed south into the
Midlands, Lincolnshire and East Anglia, with the showers
locally heavy and thundery.
22nd to 24th: A build of pressure brought drier
conditions to most parts on the 22nd. It was also locally
very warm away from the east coast with Saunton Sands
(Devon) reaching 19.6 °C. However, during the night
a weather front sank south, grinding to a halt across
southern England during the 23rd. This made for a cloud
and damp London Marathon with outbreaks of rain. A ridge
of high pressure built in the wake of the front but
it remained rather cloudy with fog patches developing
in the north on the morning of the 24th. Further fog
developed on the night of the 24th with some particularly
dense patches around the Thames Estuary.
25th to 30th: The ridge of high pressure collapsed
allowing Atlantic fronts to cross from the west on the
25th but these fronts weakened considerably with the
rain bands fragmenting as they pushed across the country.
It became warm as sunny spells developed ahead of these
fronts with a number of places in Lincolnshire passing
18 °C. High pressure reasserted itself from the
west over the 26th and 27th bringing drier conditions
across most parts. Initially it was rather cloudy, particularly
in the east, but sunshine amounts increased. There was
13 hours of sunshine recorded at Tenby (Pembrokeshire),
Falmouth (Cornwall) and Cromer (Norfolk) on the 28th,
29th and 30th respectively. Generally it was warm or
rather warm but as winds veered north-east it became
rather cold near the North Sea. Later on the 30th the
high cell began to decline allowing further weather
fronts to push in from the west.
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| Statistical details (using best
available data/estimates): Updated October 2006 |
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England & Wales Mean Temperature Series (series
began in 1914).
The final mean value for the month is 8.3 °C, which
is 0.9 °C above the 1961-1990 average, which is in
the above average category.
England & Wales Rainfall Series (series began
in 1914).
The final total for the month is 46.0 mm, which is 76%
of the 1961-1990 average, which is in the below average
category.
England & Wales Sunshine Series (series began
in 1929).
The final total for the month is 160.4 hours, which is
112% of the 1961-1990 average, which is in the above average
category.
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| Showery, bright and breezy. |
| Diary of Highlights
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West or north-westerly winds circulating around low pressure
near the Norwegian Sea was the main feature of April's
weather. Conditions were generally unsettled, but mostly
showery, and the absence of slow moving fronts and warm
and humid air masses meant that sunshine totals in the
east and south-east were well above average. The first
third of the month was particularly cold by recent standards,
with snow falling to low altitudes.
A complex area of low pressure moved east across Scotland
at the start of the month. Rain cleared to the north on
the 1st with further outbreaks of rain the next day.
As the low pressure moved to the east, cold winds from
between west and north brought sunny spells and wintry
showers for the next few days. A ridge of high pressure
brought a fine day to the south on the 4th, with the temperature
falling to -5 °C at Tulloch Bridge. This was followed
by another depression that moved from Iceland to Denmark,
with its fronts pushing a band of rain south-east on the
5th. The next few days were the coldest of the month with
the temperature reaching only 3 °C at Loch Glascarnoch
on the 7th and 4 °C at Tulloch Bridge on the 9th.
The cold was emphasised by strong winds at times with
gusts reaching 64 m.p.h. at Stornoway on the 6th. Snow
lay on the hills, reaching down to Eskdalemuir and Glenlivet
on the 8th and 9th respectively. A ridge of high pressure
brought fine weather on the night of 9th/10th, with the
temperature falling to -7 °C at Tulloch Bridge.
From the 11th to the 19th the showery theme continued
with winds blowing from just north of west, but it was
not as cold as before and snow was confined to the hills.
Fronts pushed a band of rain across the country during
the early hours of the 11th with 28 mm recorded at Broadford.
Further fronts on the 12th meant that Loch Glascarnoch
received 21 mm of rain and experienced gusts of up to
58 m.p.h. Heavy showers on the 13th gave 22 mm of rain
at Tulloch Bridge. After this the weather settled down
somewhat so that although showers continued, eastern districts
saw plenty of sun on most days.
Alternations of damp and fine conditions were experienced
from the 20th to the 24th as troughs (20th, 22nd and 24th)
and ridges (21st and 23rd) crossed the country. It was
warmer than before with the temperature rising to 15 °C
on the sunny days.
Cool, bright and showery westerly weather returned on
the 25th but soon an anticyclone built to the west of
Ireland and extended a strong ridge to Scotland. Consequently
the showers died out and many districts enjoyed a few
fine days weather towards the end of the month. Fronts
moving in from the Atlantic pushed a band of rain across
the west of Scotland on the 30th.
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Statistical details (using
best available data/estimates): Updated October 2006
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Scotland Mean Temperature Series
(series began in 1914).
The final value for the month was 5.7 °C, which is
0.2 °C above the 1961-1990 average, which is in the
close to average category.
Scotland Rainfall Series (series began in 1914).
The final total for the month was 107.9 mm, which is 134%
of the 1961-1990 average, which is in the above average
category.
Scotland Sunshine Series (series began in 1929).
The final total for the month was 171.2 hours, which is
125% of the 1961-1990 average, which is in the well above
average category. Sunniest since 1984.
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| Rainfall and temperature close to average. |
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Diary of Highlights
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The first ten days of the month saw a continuation of
the decidedly cold and wintry theme of the spring thus
far. The first three days were bright but cold with sunshine
and occasional heavy showers, some falling as hail and
accompanied by localised thunderstorms. Blustery north-west
winds accentuated the chill in many areas.
Frost became more widespread by the morning of the 4th
and 5th with many inland areas seeing dawn temperatures
between -3 and -6 °C. Cloud increased to give some
light showery rain on the afternoon of the 5th and a cold
front gave 5-10 mm on the morning of the 6th. The 7th
started bright and dry with some early ground frost but
cloud built to give heavy showers in the afternoon with
hail and thunder observed locally. The showers fell as
a wintry mix of sleet and snow on the hills. The 8th was
little different with further heavy hail showers and cold,
blustery winds. The 9th started cold with ground frost
but cloud increased to give rain, sleet and hill snow
in the afternoon when temperatures in many areas struggled
between 3 and 5 °C. Skies cleared during Sunday evening
and by the morning of the 10th another hard frost for
mid-April was occurring with daybreak temperatures again
down to between -4 and -6 °C.
The days in the run up to Easter where changeable with
some rain at times through temperatures staged a modest
recovery. The Easter holiday started sunny on Good Friday,
and with light winds and temperatures of 14 °C, it
felt pleasantly warm in many areas. Although there was
some further sunshine through the remainder of the long
holiday weekend, skies were often cloudy and showers or
showery rain became increasingly more widespread by the
18th though never in any great amounts.
The days between the 19th and 21st were more settled
with some sunshine and temperatures reached 18 °C
in some areas on the 21st in prolonged sunshine. The remainder
of the month maintained a rather changeable weather pattern
with some sunny and pleasantly warm days interspersed
with cloudy interludes with some showery rain. The wettest
period was on the evening of the 30th with up to 10 mm
or more in many places.
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Statistical details (using
best available data/estimates): Updated October 2006
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Northern Ireland Mean Temperature Series (series
began in 1914).
The final value for the month was 7.3°C, which is
0.3 °C above the 1961-1990 average, which is in the
close to average category.
Northern Ireland Rainfall Series (series began
in 1914).
The final total for the month was 72.9 mm, which is 109%
of the 1961-1990 average, which is in the close to average
category.
Northern Ireland Sunshine Series (series began
in 1929).
The final total for the month was 163.8 hours, which is
112% of the 1961-1990 average, which is in the above average
category.
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| Homogeneous
series based upon selected station data: |
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Central England Temperature (series begins in
1659).
CET
Index
England and Wales Rainfall (series begins in 1766).
EWP
Index
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| Note: All values are provisional based
on data available at the time. |
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