Here is a summary of the NWP output for 12z on Sunday.
Issued 0552z, 24th January 2007.

After the weekend things will turn much milder across the UK as a strong
zonal flow develops to the north. The coldest conditions are likely across
central and southern aresa of the UK by night, closer to the Azores High.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
http://85.214.49.20/pics/avnpanel1.gif
High pressure lies to the west, leading to a mixture of northerlies and
NW'lies for the UK. A ridge sinks over Scotland and Northern Ireland
tomorrow, with the winds veering NNE'ly elsewhere. Friday sees NW'lies for
all as the ridge continues to sink southwards, followed by further NW'lies
on Saturday.

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 the UK under a ridge, with a shortwave trough
further west. At the 500hPa level there's an upper high to the immediate SW
of Ireland, with a NW'ly gradient over the UK. MetO and ECM also show an
upper high to the SW, as is the case with GEM and NGP. JMA has an upper high
over Ireland instead.
At the surface GFS brings WNW'lies for all with a large high to the south.
MetO shows the high to the SW of Ireland, again with NW'lies for the UK. ECM
has stronger NW'lies for all as the high's further SE. JMA has the high over
Ireland with NW'lies, while GEM and NGP bring WNW'lies with the high further
south.

Evolution to T+168
ECM shows the Azores High stationary over Biscay. Day 6 sees a ridge cross
the UK with NW'lies in advance and SW'lies following behind, followed by
WSW'lies for all on day 7.
GFS keeps the high a bit further north, with a strongly zonal flow to the
north of the UK. A mixture of westerlies and WSW'lies covers the UK on
Tuesday, followed by further WSW'lies on day 7.

Looking further afield
ECM shows the Azores High transferring NE'wards. On day 8 it's still to the
SW with WNW'lies for the UK, followed by lighter NW'lies on day 9 as it
crosses Ireland and Wales. Day 10 sees the high build over Scandinavia,
introducing ESE'lies for southern England with southerlies elsewhere.
GFS also has the Azores High moving NE'wards, albeit not in as dramatic a
fashion as ECM. Day 8 sees WNW'lies for all, followed by southerlies and
SSW'lies for Northern Ireland on Scotland on day 9 as the high crosses
England and Wales. On day 10 the high builds eastwards, leading to SW'lies
for Scotland and Northern Ireland with light winds elsewhere.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show much milder air aloft across the UK, followed by a
probable cooler spell during the first week of February.