Here is a summary of the NWP output for noon (GMT) on Monday.
Issued 0456z, 11th September 2008

The middle of next week is likely to see wet weather over much of England 
and Wales, with low pressure nearby. Elsewhere the risk of rain is lower due 
to high pressure to the north. Towards the end of the week the models split 
once again, with GFS bringing more settled conditions and ECM keeping the 
north/south divide going.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
A deep low lies to the west of Scotland, with strong southerlies over the 
UK. Tomorrow the low moves northwards, leaving a trough and WSW'lies over 
the UK. Saturday sees a col and the col persists on Sunday.

T+120 synopsis
http://85.214.49.20/pics/Rtavn12014.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 weak trough over the UK, with a ridge over the 
western Atlantic. At the 500hPa level there's a SW'ly flow, with a trough to 
the NW. An upper col covers the UK with MetO, while ECM also has a col. GEM 
shows upper SW'lies.
At the surface GFS brings a col for most, with light NW'lies over Northern 
Ireland. MetO has a col too, as does ECM. GEM has low pressure over Scotland 
and a trough over the rest of the UK, with WNW'lies.

Evolution to T+168
Day 6 with ECM brings ENE'lies as a weak trough covers the UK. On day 7 the 
winds become NE'lies, with a ridge over Scotland.
Northerlies cover the UK on day 6 with GFS, with low pressure over Kent. The 
low deepens over London on day 7, with strong easterlies and ENE'lies over 
the UK.

Looking further afield
On day 8 with ECM NE'lies continue to affect England and Wales, with 
Scotland and Northern Ireland under a ridge. There's little change on day 9, 
although an upper cold pool over the near Continent would bring organised 
rain for SE England. NE'lies persist on day 10.
A ridge covers the UK on day 8 with GFS, with ENE'lies for most and SE'lies 
for Northern Ireland and western Scotland. On day 9 the winds become 
NNW'lies as a ridge moves in from the west and on day 10 the ridge moves 
over Scotland and Northern Ireland, with northerlies elsewhere.

Ensemble analysis 
(http://91.121.94.83/modeles/gens/graphe_ens3.php?x=306&ext=1&y=141&run=0&ville=Londres)
The ensembles show an increasingly cool and wet outlook.