Here is a summary of the latest NWP output for noon (GMT) on Sunday.
Issued 0427z, 18/08/10.

The first half of next week looks like seeing changeable weather move
across the UK from the Atlantic, with moderate to strong WSW'lies. All
areas will see rain, heaviest and most frequent in the north and west.

ECMWF: http://www.wzkarten.de/pics/Recm1201.gif
Low pressure lies to the west, with southerlies for all. The low
deepens and moves NE'wards on day 6, with stronger and fresher SW'lies
as a result. On day 7 the low deepens further over the Northen Isles,
with strong WSW'lies for the UK.

MetO: http://www.wzkarten.de/pics/Rukm1201.gif
The Met Office run shows SSW'lies due to a low to the west. The low
deepens over Scotland on day 6, with SW'lies for England and Wales and
NW'lies for Northern Ireland.

GFS: http://www.wzkarten.de/pics/Rtavn1201.png
SSW'lies cover the UK as the result of a low to the NW. A trough moves
eastwards on day 6, bringing WSW'lies. There's little change on day 7
as a low transfers slowly ENE'wards to the north.

GEM: http://www.wzkarten.de/pics/Rgem1201.gif
The UK lies under SW'lies with a low to the north.

JMA: http://www.wzkarten.de/pics/Rjma1201.gif
The Japanese run shows a weak ridge over England and Wales, with a
mixture of SSW'lies and SW'lies for the UK.