Here is a summary of the NWP output for noon (GMT) on Sunday.
Issued 0512z, 21st May 2008

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
SE'lies cover the UK, with a ridge to the east. SE'lies persist tomorrow as
a trough moves over Ireland, By Friday ESE'lies affect the UK and Satureday
sees low pressure deepen over Biscay, resulting in easterlies 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/Rukm1201.gif
http://85.214.49.20/pics/Recm1201.gif /
http://www.meteociel.fr/modeles/nogapse_cartes.php
The jetstream chart shows a large trough over the UK, with a ridge to the
west. At the 500hPa level there's a ridge to the NE and a low to the SE,
with upper NE'lies. MetO has a col aloft while ECM brings NE'lies aloft as
per GFS. GEM has a ridge over the UK.
At the surface GFS brings strong NE'lies with a high to the north and a
ridge over Scotland. MetO shows strong NE'lies too, again with a high to the
north. ECM brings strong ENE'lies and a high to the NNW, as is the case with
GEM.

Evolution to T+168
Day 6 with ECM brings NE'lies for all as pressure remains high to the NW.
The high declines as it moves over the UK on day 7, with light winds for
all.
GFS brings a ridge over Scotland and Northern Ireland on day 6, with NE'lies
elsewhere. The ridge moves away to the east on day 7, allowing southerlies
to affect Scotland and Northern Ireland. Elsewhere winds are light due to a
col.

Looking further afield
On day 8 with ECM a ridge covers much of the UK, although SE England lies
under NE'lies. Much the same is true on day 9, although the NE'lies affect
much of England and Wales. Day 10 sees light northerlies as the high
declines to the west.
GFS shows a col and light winds on day 8. On day 9 NW'lies cover the UK,
with a ridge to the west. By day 10 a ridge covers the UK, with SW'lies for
Scotland and Northern Ireland; elsewhere winds are NW'lies.

Ensemble analysis
(http://91.121.94.83/modeles/gens/gra...ille=Lon dres)
The ensembles show a prolonged average or above-average spell of
temperatures coming up.

In summary...
Bank Holiday Monday looks like seeing a NW/SE split, with gusty NE'lies over
much of the UK. In the north and NW it'll be largely dry, but further south
there's a greater risk of rain from a low pressure just to the south. Beyond
that GFS shows a ridge "toppling" over the UK, before dissipating by the end
of the week. ECM on the other hand keeps the high around for longer, ending
up with a NW/SE split again (with the north and west under the high).