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Old December 2nd 07, 06:54 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 2007: Synoptic Overview

The dominant weather types during November were
anticyclonic and northwesterly, although there was a short
cyclonic episode between the 17th and 21st, while a
disturbed westerly type appeared to have set in at the
month's end. The bulk of the month's rain fell during the
cyclonic spell, otherwise it was largely dry. Sunshine was
plentiful over most of England and Wales, especially in
eastern districts, but there was a marked shortage in
northern and western Scotland and Northern Ireland.
This was the fourth consecutive 'anticyclonic' month.



Mean pressure charts are available at:
Charts: http://www.climate-uk.com/monpre/0711.htm
The Monthly Review will shortbly be uploaded to:
http://www.climate-uk.com/monthly/0711.htm
Graphs: http://www.climate-uk.com/graphs/0711.htm and
http://www.climate-uk.com/graphs/200711.htm
Not The Long Range Forecast should be available by Dec 4 on:
http://www.climate-uk.com/page4.html


The mean sea-level chart is dominated by a broad zone of high
pressure extending across the Atlantic and Europe between
latitudes 40 and 55 degN, with a centre of 1024mbar located
approx 1000km SW of Ireland (at 48N 18W). The Icelandic
low was almost absent, with lowest pressure of 999 mbar in
the Barents Sea. Aloft, there were broad troughs around
longitude 40-50W and and 20-30E, and a broad ridge at
10-20W. The surface flow over the British Isles was NW-ly
.... and the N'ly component to the flow was the highest in Nov
since 1996; it ranked 14th most 'northerly' in 135 yrs of records.

The sea-level pressure anomaly field showed a huge area of
above-normal area over most of the northern Atlantic and the
western half of Europe. Pressure was below normal over eastern
Europe, in the Barents Sea, Svalbard, and the Russian Arctic,
and also south of the Azores.


The main anomaly centres we
+10mbar west of Ireland (53N 23W)
- 6mbar over Svalbard
- 4mbar between Moscow and St Petersburg


Over the British Isles pressure anomaly ranged from +4mbar
in Shetland to +8mbar along the west coast of Ireland, and the
anomalous flow was N-ly.


CET (after Manley) 7.18°C (+0.3 degC wrt 1971-2000)
CET (after Hadley) 7.3°C (+0.4 degC)
E&W Rain (provisional): 77.2mm ( 77% of 1971-2000 mean)
E&W Sunshine (prov): 74.9 hr (113% of 1971-2000 mean)


CScotT: 7.5°C (+1.6 degC)
ScotRain: 109mm (112%)
ScotSun: 47hr ( 90%)


NIT: 9.0°C (+2.1 degC)
NI Rain: 69mm ( 78%)
NI Sun: 34hr ( 59%)


Rainfall totals ranged from 244mm at Loch Shin (Sutherland)
to 26mm at Coningsby (Lincs)


Percentages ranged from 165 at Kinloss (Morayshire) to
39 at Marham (Norfolk).


Sunshine totals ranged from 106.1h at Southampton -
presumed KZ sensor - to 19.7h at Stornoway (KZ sensor).


Percentages ranged from 154 at Luton (Beds)
to 45 at Tiree Stornoway

(c) Philip Eden