Here is a summary of the NWP output for 12z on Monday.
Issued 0546z, 11th January 2007.

A spell of very unsettled weather is likely next week, with all areas seeing
gales and heavy rain at times.

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 deep low lies to the NW with strong to gale force SW'lies over the UK. The
low moves slowly ENE'wards tomorrow, leaving the UK under a weak ridge and
less strong westerlies. WSW'lies affect the UK on Saturday, before another
weak ridge brings further westerlies on Sunday.

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 marked shortwave pattern over the North Atlantic
with the UK under a ridge. The jet runs NE'wards over Scotland and Northern
Ireland. At the 500hPa level there's a SW'ly gradient over the UK, with an
upper ridge over the Alpa and an upper low to the north of the UK. MetO is
very similar to GFS, while ECM has lower heights to the NW but still a SW'ly
gradient. JMA is unavailable today, while GEM has an upper ridge over the
North Sea, with higher heights for the UK than the other runs. NGP has a
WSW'ly gradient, with upper lows well to the NNE and NW.
At the surface GFS brings SW'lies and WSW'lies, moderate for England and
Wales but gale force for Scotland and Northern Ireland. MetO has a weak
ridge over Ireland which mitigates the wind strength over Scotland,
otherwise it's very similar to GFS with WSW'lies and SW'lies. ECM shows
SW'lies for all ahead of a trough to the west, as does NGP. The Canadian run
has a stronger ridge over the North Sea and a mixture of SW'lies and
SSW'lies for the UK.

Evolution to T+168
ECM shows a deep upper low moving slowly eastwards from west of Greenland to
Iceland by day 7. A mixture of southerlies and SSW'lies cover the UK on day
6 as a secondary low moves NE'wards to the south of Ireland. By day 7 SSW'ly
gales cover the UK in association with deep lows linked to the deep upper
low near Iceland.
GFS keeps the main upper low in the vicinity of Greenland, not transferring
it eastwards as with ECM. Day 6 sees a deep low west of Scotland and SW'ly
gales for all, followed by strong SSW'lies ahead of another low on day 7.

Looking further afield
Beyond T+168, ECM shows westerlies for days 8 to 10, with complex low
pressure near Iceland slowly transferring eastwards.
GFS shows a shortwave pattern persisting, but with the UK under a trough on
the "cold side" of the jet by day 10. Day 8 sees a deep low to the north and
a mixture of westerly and SW'ly gales. Southerlies affect the UK on day 9
with a deep low to the west, followed by WNW'lies and westerlies on day 10
as the main low moves eastwards over Denmark.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a "sine wave" effect as warm sectors cross the UK. Longer
term the 850s trend below average, but in recent days that's been the case
only for the 850s to rise nearer the time.