Here is a summary of the NWP output for 12z on Monday.
Issued 0501z, 16th May 2007.

It's now looking like the first half of next week will continue the
changable theme for much of the UK, with low pressure to the north and a
ridge over Biscay and France. As the week progresses the ridge will move
slowly northwards, bringing warmer conditions for southern areas of the UK.
Northern and northwestern areas will probably stay cloudier and less
settled.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
http://85.214.49.20/pics/avnpanel1.gif
Winds are light across Scotland with westerlies elsewhere associated with a
plume of tropical air. A low deepens to the WNW tomorrow, bringing SW'lies
across the UK. By Saturday the low moves ENE'wards to the north of the UK,
with strong SW'lies for most. The SW'lies ease a little on Sunday as the low
fills.

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 strong jet across the North Atlantic with a
marked shortwave pattern near the UK. At the 500hPa level there's a trough
over the UK with GFS. ECM shows a trough to the west, as does MetO. GEM is
very similar to MetO, while NGP brings a trough over the UK in a similar
fashion to GFS.
At the surface GFS brings SW'lies for all with a deep low to the north. MetO
shows SW'lies for Scotland and Northern Ireland with a ridge and light winds
elsewhere. ECM also shows a ridge for England and Wales with SW'lies
elsewhere. GEM shows WSW'lies and SW'lies over the UK with the ridge over
the Channel. NGP shows the ridge further south still, with SW'lies for all.

Evolution to T+168
ECM brings SW'lies for the UK on days 6 and 7 with a ridge persisting over
France.
GFS shows WSW'lies and a ridge over France on day 6. On day 7 the ridge
moves NE'waeds, bringing light winds to SE England and SW'lies elsewhere.

Looking further afield
Day 8 on the ECM shows westeries as the ridge persists over France. On day 9
a ridge builds over England and Wales with SW'lies elsewhere. By day 10 the
ridge moves back over France with WSW'lies for the UK.
GFS shows a col for England and Wales on day 8 with a trough bringing
SW'lies for Scotland and Northern Ireland. The trough crosses the UK on day
9, with southerlies in advance and NW'lies following behind. By day 10
northerlies and NW'lies cover the UK, with a ridge to the west.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a heatwave on the way.