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Old December 1st 08, 01:07 PM posted to uk.sci.weather
Philip Eden Philip Eden is offline
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First recorded activity by Weather-Banter: Jul 2003
Posts: 6,134
Default November 2008: Synoptic Overview

A NE-ly type lasted for most of the first week, but the
remainder of the month brought an alternation of westerly and
northerly spells. It was the most 'northerly'(1) November
since 1971 and the eighth most northerly in 136 years of
records. It was noteworthy, therefore, that the mean monthly
temperature was close to or slightly above the 1971-2000
mean in all regions of the British Isles. Regionally, rainfall was
below normal except in the Midlands and the Southeast,
while sunshine totals were near or below normal except in
eastern Scotland and northeast England where they were
markedly above.

(1) As measured by the magnitude of the northerly
component of the surface flow over the lat/long square
50-60N, 00-10W.

Mean pressure charts have already been uploaded to:
Charts: http://www.climate-uk.com/monpre/0811.htm
The Monthly Review will be uploaded later today to:
http://www.climate-uk.com/monthly/0811.htm
Graphs: http://www.climate-uk.com/graphs/0811.htm and
http://www.climate-uk.com/graphs/200811.htm
Not The Long Range Forecast should be available by Dec 4 on:
http://www.climate-uk.com/page4.html

The sea-level pressure chart shows the Icelandic low much
deeper than usual and displaced far to the NE of its normal
position, with a centre of 996mbar near North Cape. The
Azores high is slightly north of its normal position and markedly
more intense than usual at 1028mbar. Pressure is relatively
low in the western Mediterranean. The surface flow over the
British Isles is NW-ly.


At the 500 mbar level there is a marked ridge at
30-40degW and a marked trough at 10-20degE.

The sea-level pressure anomaly field is dominated by a huge
area of above-average pressure covering practically the whole
of the North Atlantic north of latitude 30degN. Pressure is
also above average over the Black Sea area. A zone of
below-normal pressure extends from NW Africa across the
western Med, France, Germany and central Europe, to the
Baltic, Finland and the Barents Sea.

The main anomaly centres we
+17mbar in mid-Atlantic at 51N 32W
+ 4mbar over the Black Sea
- 8mbar over Finland
- 4mbar over Switzerland
- 4mbar over the Balearic Is

Over the British Isles pressure anomaly ranges from -3mbar
over east Kent to +3mbar in western Ireland. The anomalous
flow is northerly.

CET (after Manley) 7.03°C (+0.1 degC wrt 1971-2000)
CET (after Hadley) prob 7.1°C
E&W Rain (provisional): 90.6mm ( 91% of 1971-2000 mean)
E&W Sunshine (prov): 63.8hr ( 96% of 1971-2000 mean)

It was the coldest November over England and Wales since
2005, and the cloudiest since 2004. It was wetter than 2007
but not as wet as 2006.

CScotT: 6.1°C (+0.2degC)
ScotRain: 82mm ( 75%)
ScotSun: 60hr (110%)

NIT: 7.5°C (+0.2degC)
NI Rain: 68mm ( 71%)
NI Sun: 58hr ( 97%)

Rainfall totals ranged from 313mm at Loch Shin (Sutherland)
and 303mm at Kinlochewe (Wester Ross) to 27mm at Leuchars
(Fife) and 32mm at Gogarbank (nr Edinburgh). [Also 26mm at
Durham, but the data look faulty to me].

Percentages ranged from 153 at Manston (Kent) to
34 Charterhall (Berwickshire).

Sunshine totals ranged from 99.5h at Leuchars (Fife)
to 19.6h at Stornoway (W.Isles) and 29.3h at Tiree
(Inner Hebrides) [all KZ sensors]. A total of 112.2h
was also noted at Berwick-upon-Tweed [sensor not
known].

Percentages ranged from 146 at Church Fenton
near York) to 43 at Stornoway.

(c) Philip Eden