Here is a summary of the latest NWP output for noon (GMT) on Sunday.
Issued 0433z, 8/09/10.

The southernmost areas of the UK will see settled and warm weather to
start next week, with rain further north. The models are split after
that: GFS shows the warm, dry weather spreading northwards while MetO
and ECM show a trough moving across the UK instead. The far south
looks like staying largely dry throughout.

ECMWF: http://www.wzkarten.de/pics/Recm1201.gif
A ridge covers the UK, bringing northerlies to England and Wales and
SW'lies elsewhere. SW'lies spread across all areas except the far
south on day 6, as pressure falls to the NW. On day 7 a trough crosses
the UK, with westerlies for all.

MetO: http://www.wzkarten.de/pics/Rukm1201.gif
The Met Office run shows a ridge over England and Wales, with light
westerlies. Further north winds are SW'ly, with low pressure over
Iceland. On day 6 SW'lis strengthen over all areas except southern
England, as high pressure declines to the south.

GFS: http://www.wzkarten.de/pics/Rtavn1201.png
The UK lies under westerlies and WSW'lies, with a large high to the SW
and a ridge over England and Wales. The winds become WSW'lies for most
on day 6 as the high approaches the UK. On day 7 the high covers the
Celtic Sea, leading to a mixture of NW'lies and westerlies for the UK.

GEM: http://www.wzkarten.de/pics/Rgem1201.gif
A ridge lies to the west, resulting in northerlies for all.

JMA: http://www.wzkarten.de/pics/Rjma1201.gif
JMA shows a ridge over the UK, with a mixture of westerlies and
NW'lies as a result.