Here is a summary of the latest NWP output for noon (GMT) on Wednesday.
Issued 0505z, 4th July 2009.

The latter half of the working week will see a relatively cool NW'ly flow
over the UK, with showers or longer spells of rain for many areas driven in
by a low to the NE. Southern and (especially) southeastern areas will escape
much of the rain, however. Temperatures will range from rather below normal
in the north to near normal in the south.

ECMWF: http://www.wzkarten.de/pics/Recm1201.gif
The European model brings high pressure to the NW and SW, with low pressure
over Scandinavia. The UK lies under a moderate NW'ly flow as a result. The
NW'lies ease somewhat as the high to the NW declines and sinks SE'wards. By
day 7 the remnants of the high cross the UK, with westerlies as a result.

MetO: http://www.wzkarten.de/pics/Rukm1201.gif
Unavailable today.

GFS: http://www.wzkarten.de/pics/Rtavn1201.png
Complex low pressure covers Scandinavia, with a NW'ly flow over the UK.
NW'lies persist on days 6 and 7 for most, although by then southenmost areas
lie under a col and light winds.

GEM: http://www.wzkarten.de/pics/Rgem1201.gif
The Canadian run brings NW'lies for all, with a low to the NE and a col to
the west.

JMA: http://www.wzkarten.de/pics/Rjma1201.gif
The Japanese run shows WNW'lies for all and again, a low to the NE.