Here is a summary of the NWP output for 12z on Tuesday.
Issued 0553z, 12th October 2007

The middle of the week will see settled conditions for England and Wales, as
a large ridge moves across the UK towards Scandinavia. Scotland and Northern
Ireland will be at greater risk of seeing cloud and rain, especially in the
NW. Temperatures will be closer to average than at present, with somewhat
cooler air aloft.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
A large high lies to the south of the UK, with a ridge over the British
Isles. Tomorrow the high builds NE'wards, leading to southerlies for
Northern Ireland and Scotland. Elsewhere winds are light. On Sunday a ridge
persists over England and Wales, with SSW'lies elsewhere. Monday sees a
trough move eastwards over the UK, with southerlies for all.

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.gif /
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 trough in the vicinity of the UK, with a weak
ridge to the west. At the 500hPa level there's a westerly gradient aloft,
while ECM has an upper trough over the UK instead. GEM has a very weak
trough over the UK and NGP brings an upper high over the SW approaches, with
a ridge over the UK.
At the surface GFS brings a weak ridge over the UK, with SW'lies for
Scotland and Northern Ireland and light winds elsewhere. ECM shows a trough
over the Irish Sea, with WSW'lies in advance and WNW'lies following behind.
GEM brings westerlies and a weak trough, while NGP centres high pressure
over Kent with a ridge over England and Wales; Scotland and Northern Ireland
are affected by brisk southerlies.

Evolution to T+168
ECM shows an upper ridge building towards the UK from the SW on day 6, with
a surface ridge moving NE'wards over the UK. Winds are light for most, with
moderate WNW'lies for NE Scotland. On day 7 strong southerlies affect NW
Scotland and Northern Ireland as pressure builds across the UK.
GFS brings strong and warm southerlies over Scotland and Northern Ireland on
day 6, with southerlies and SE'lies on day 7 as high pressure builds to the
east.

Looking further afield
The ECM shows high pressure over Scandinavia on day 8, with a ridge over
England and Wales. Southerlies cover Scotland and Northern Ireland and
there's little change on day 9. By day 10 a col covers the UK, with light
winds for most.
GFS on day 8 shows SE'lies for all, with a high to the east and a low to the
west. Trough disruption occurs on day 9, with ESE'lies over the UK and on
day 10 the trough moves northwards again, with SE'lies across the UK.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles for London show four more dry and warm days, followed by some
rain on the 16th. After that it looks largely dry, albeit cooler.