Here is a summary of the NWP output for noon on Thursday.
Issued 0533, 21st Jan 2008

The weekend looks like seeing a north/south split, with plenty of wind and
rain over Scotland and Northern Ireland. Elsewhere winds will become lighter
due to high pressure over Biscay and rainfall amounts over southern parts of
the UK will be small in comparison to the north. Temperatures are likely to
be on the mild side, but not as exceptionally mild as it has been in the
south recently.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
SW'lies and westerlies cover the UK, with a ridge to the NW and lows to the
west and north. A ridge moves eastwards over Scotland and Northern Ireland
tomorrow, with NW'lies elsewhere. SW'lies and SSW'lies cover the UK on
Wednesday as high pressure builds to the SE, followed by further SW'lies on
Thursday.

T+120 synopsis
http://85.214.49.20/pics/Rtavn12015.png /
http://85.214.49.20/pics/Rtavn1201.png
http://85.214.49.20/pics/Rukm1201.gif
http://85.214.49.20/pics/Recm1201.gif /
http://www.meteociel.fr/modeles/nogapse_cartes.php
The jetstream chart shows a very strong and zonal jet over the UK and much
of the North Atlantic. At the 500hPa level there's a high over Biscay and a
strong westerly flow aloft. MetO shows a similar picture, with a large upper
high over Biscay. ECM centres the upper high further west, but there are
still upper westerlies over the UK. NGP shows upper WNW'lies and an upper
high lies to the NE of the Azores. GEM shows upper westerlies and a high
over Iberia.
At the surface GFS brings strong SW'lies and WSW'lies, with a deep low to
the north and a high over Biscay. MetO shows strong WSW'lies for all,
without the secondary low that GFS features. There's still a large high over
Biscay, as is the case with ECM (which shows strong westerlies and WSW'lies
for the UK). NGP has westerlies for all with the UK between a trough to the
east and a weak ridge to the west. GEM brings strong westerlies for all
with complex low pressure to the north and a high over northern Spain.

Evolution to T+168
ECM shows westerlies on day 6 with pressure remaining high over Biscay.
There's little change on day 7 as the high drifts slowly eastwards.
GFS brings high pressure over Biscay on day 6, with moderate westerlies over
the UK. SW'lies and WSW'lies cover the UK on day 7 with high pressure moving
slowly eastwards over France.

Looking further afield
By day 8 ECM shows the high to the SE declining slowly, with SW'lies across
the UK. The winds become WSW'lies and westerlies on day 9 as a trough moves
eastwards, followed by SW'lies on day 10.
GFS shows high pressure to the SE on day 8, leading to SW'lies for all. High
pressure builds over Ireland on day 9, with light NW'lies and NNW'lies for
the UK. By day 10 the high builds to the east, with southerlies and SSW'lies
across the UK.

Ensemble analysis
(http://91.121.94.83/modeles/gens/gra...ille=Lond res)
The ensembles continue to show a zonal "sine wave" pattern, with 850s
reaching a mean of +10C over southern England around T+132.