Here is a summary of the latest NWP output, for noon (GMT) on Saturday.
Issued 0559z, 23/09/03.

ECMWF: http://www.wetterzentrale.de/pics/Recm1201.gif
A ridge covers the UK, bringing light easterlies for southern England and
light northerlies elsewhere. The ridge declines over the UK at T+144,
although a small low over Brest brings moderate easterlies to southern
England and Wales. By T+168 the low moves eastwards, leaving northerlies
over much of England. The rest of the UK lies under westerlies, from an
elongated low to the north of the UK.

MetO: http://www.wetterzentrale.de/pics/Rukm1201.html
Northerlies cover much of the UK, due to a ridge to the west and low
pressure over southern Scandinavia. The northerlies continue at T+144 as
another low moves NNE'wards to the east of the UK.

GFS: http://www.wetterzentrale.de/pics/Rtavn1081.gif
A deep low lies to the ESE of Shetland, leading to strong NW'lies over NE
Scotland. The rest of the UK lies under lighter NNW'lies and westerlies. The
NNW'lies persist at T+120 as the low fills in situ, with 850hPa temperatures
ranging from -3C over NW Scotland to +1C over southern England. A ridge
moves over England at T+144, with northerlies for England and westerlies
elsewhere. Westerlies move across the whole of the UK at T+168, with low
pressure to the south of Iceland. The low moves SE'wards and fills over the
UK on day 8, with light cyclonic winds for all. The low moves slowly
SE'wards on day 9, with the only winds of note being southerlies over
Northern Ireland. Another low moves SE'wards over Greenland to the NW of
Iceland, as pressure rises over Greenland. On day 10, high pressure
stretches from Greenland to the Azores, while the new Icelandic low merges
with the low over the UK, forming a slack low over the English Channel.
Light easterlies cover the UK as a result.

GEM: http://www.wetterzentrale.de/pics/Rgem1201.gif
Scotland lies under moderate westerlies from the Icelandic Low, while the
rest of the UK lies under lighter westerlies and northerlies, from a ridge
over England and Wales. 850hPa temperatures range from +1C over Wales,
northern England and southern Scotland to +5C over the Western Isles.
Westerlies cover all of the UK at T+144, as the Icelandic low moves NE'wards
and deepens.

JMA: http://www.wetterzentrale.de/pics/Rjma1201.html
The Japanese run shows northerlies over the UK, from a high over Ireland.
850hPa temperatures range from -3C over NE Scotland to +1C over southern
England. The high declines and sinks SE'wards at T+144, bringing mainly
light westerlies across the UK. The winds become moderate SW'lies at T+168,
with a trough west of Ireland.

Model overlay charts (GEM/GFS/JMA):
http://expert.weatheronline.co.uk/da.../ens/pslv.html
The T+108 chart shows a northerly flow over the UK, with low pressure over
Scandinavia.

In summary, today's runs suggest a northerly flow is likely over the UK this
weekend, with a large high at 50N to the west and low pressure over
Scandinavia. For the beginning of next week, there's more variance in the
runs, although there are signs of the Atlantic high ridging northwards to
Greenland, with a cool flow maintained over the UK. As ever, more runs are
needed.