Here is a summary of the NWP output for 12z on Saturday.
Issued 0530z, 30th January 2007.

Sunday and the first few days of next week are likely to be dry for most,
with high pressure close by. Some relatively cool air will be pulled down
from the north as the Azores High ridges towards Greenland. The models very
widely regarding the fate of the ridge though, with the GFS collapsing it
almost instantly and ECM showing it taking a few days longer to break down.
MetO only goes out to T+144, but the ridge looks stronger compared to GFS
and ECM at the same time period. There remains a chance of a cold spell, but
the odds are very much in favour of it becoming a cool snap, followed by a
return to milder conditions.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
http://85.214.49.20/pics/avnpanel1.gif
A mixture of westerlies and WSW'lies covers the UK, with high pressure over
Ireland. The high declines and moves SW'wards tomorrow, allowing WSW'lies to
affect all areas. By Thursday the winds become westerlies as a ridge
approaches from the west, followed by further westerlies for Northern
Ireland and Scotland on Friday. By then England and Wales lie under NW'lies
due to a ridge over Ireland and the Irish Sea.

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/Rjma1201.gif /
http://85.214.49.20/pics/Rukm1201.gif
http://85.214.49.20/pics/Recm1201.gif /
http://85.214.49.20/pics/Rngp1201.gif
The jetstream chart shows a shortwave pattern over the North Atlantic, with
the UK under a ridge. A very strong jet is emerging from the eastern
seaboard. At the 500hPa level there's an upper ridge atop the UK, while ECM
has the ridge further to the SW (as is the case with MetO). MetO shows much
higher heights over Greenland compared to the other two major models. JMA
has an upper ridge to the south of the UK, while NGP has a high centred over
England. GEM shows an upper high over western France.
At the surface GFS shows a high bringing light winds to much of the UK,
while ECM has the high further SW with westerlies and WSW'lies for the UK.
MetO also shows a high to the SW with westerlies and JMA brings WSW'lies and
SW'lies with high pressure over the English Channel. NGP shows high pressure
over East Anglia, bringing light winds to England and Wales with southerlies
and SW'lies elsewhere. Finally GEM has high pressure to the south, with a
mixture of WSW'lies and SW'lies as a result.

Evolution to T+168
ECM shows an upper ridge progressing eastwards and declining. On day 6 The
Azores High ridges northwards, drawing in WNW'lies for all. By day 7 the
high moves over Biscay, with a ridge over Ireland. NW'lies are the result
across the UK.
GFS is more progressive. On day 6 a WNW'ly flow covers the UK with the
Azores High to the WSW. The ridge collapses on day 7, allowing further
WNW'lies to cover the UK.

Looking further afield
ECM shows low pressure to the west on day 8 and a col over much of the UK.
The low deepens in situ on day 9, with a trough moving northwards across the
UK. Winds are ESE'lies for all as a result. Day 10 sees the trough move
northwards, leading to SSW'lies across much of England and Wales. Elsewhere,
in colder air, Scotland and Northern Ireland lie under ESE'lies.
GFS shows a mobile setup, driven by a strong jet. WSW'lies cover the UK on
day 8 due to a low to the NW, followed by further WSW'lies on day 9 as the
low moves eastwards. Day 10 sees lows to the NE and NW with westerlies for
all.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a shortlived cool interlude followed by a return to mild
conditions.