Here is a summary of the NWP output for 12z on Wednesday.
Issued 0531z, 18/11/06

As with the past few days, the outlook is unsettled and largely mild, again
due to cloudy nights more than excessively warm days.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
http://85.214.49.20/pics/avnpanel1.gif
SW'lies cover the UK, with low pressure to the north and a secondary low to
the west of Scotland. SW'lies persist tomorrow, followed by strong to gale
force SSW'lies on Monday from a deep low to the NW. Tuesday sees WSW'lies as
the low moves slowly eastwards.

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/Rjma1201.jpg /
http://85.214.49.20/pics/Rukm1201.jpg
http://85.214.49.20/pics/Recm1201.jpg /
http://85.214.49.20/pics/Rngp1201.jpg
The jetstream chart shows a poweful and zonal jet across the North Atlantic,
with the UK under a shallow trough - the jet passes over Biscay and France.
At the 500hPa level there's also a trough over the UK, as is the case with
MetO. ECM keeps the trough further west, while NGP instead shows a weak
ridge over the UK with a marked trough over Italy instead. JMA shows a weak
trough for the UK and the Canadian run brings a weak ridge.
At the surface, GFS brings light westerlies with a trough over the North
Sea; there's a deep low to the north. MetO is similar synoptically but this
time the winds are light WNW'lies instead. ECM has a low to the west of the
UK with mainly light SW'lies and southerlies for the UK; the exception is
southern England which lies under strong westerlies. NGP shows WSW'lies for
all with lows to the NE and NW, while JMA has a trough over the North Sea
and westerlies as a result. Finally the Canadian run shows a trough overr
Ireland, with SW'lies for all.

Evolution to T+168
ECM shows an upper trough developing to the west. Low presure crosses
Scotland at T+144, bringing a trough over Ireland and NW'lies there.
Elsewhere winds are WSW'lies, followed by WSW'lies for all from a weak ridge
at T+168.
GFS as ever is somewhat different with an upper trough developing over
Iberia. At T+144 a very deep low covers northern France, bringing NE'ly
gales across SE and central England. Elsewhere winds are much lighter and
from the NW or north. By T+168 low pressure deepens over Biscay with complex
low pressure east and west of the UK. Winds are mainly light westerlies for
most as a result.

Looking further afield
ECM out to 10 days brings a deep low over the UK on day 8 with strong
SW'lies for England and Wales; elsewhere winds are southerlies or SE'lies.
On day 9 a strong SSW'ly flow affects the UK and by day 10 there are further
SSW'lies with low pressure to the west.
The GFS shows SW'lies for the UK on day 8 as the result of low pressure to
the west. A secondary low moves along the English Channel on day 9 with
easterlies and NE'lies for the UK, followed by NW'lies on day 10 as the low
moves NNE'wards.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a jumbled mess of spaghetti from T+120 onwards, but the
picture is very much one of low pressure in control.