Here is a summary of the NWP output for 12z on New Year's Eve.
Issued 0502z, 27th December 2006.

The models continue to show zonality returning at the weekend, with all
areas seeing a fair bit of wind and rain. Temperatures will be generally
mild for England and Wales, nearer average further north but still with some
mild interludes.

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 ridge covers England and Wales, with southerlies or SSE'lies over Scotland
and Northern Ireland. SW'lies and WSW'lies affect the UK tomorrow as a
shallow low crosses Scotland. Friday sees strengthening southerlies as low
pressure deepens to the west, followed by strong to gale force southerlies
on Saturday as a secondary low passes close to Scotland.

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 strong jet across the North Atlantic and
southern areas of the UK. At the 500hPa level there's a strong WSW'ly
gradient over the UK, with a trough over the North Atlantic. ECM and MetO
are very similar to each other, showing a SW'ly gradient aloft and a trough
to the west. The minor runs show a similar pattern with an upper SW'ly
gradient over the UK.
At the surface GFS brings strong westerlies across the UK, with a low over
the Northerm Isles. MetO and ECM show low pressure to the west of Scotland,
leading to SW'lies for the UK. JMA and GEM are similar and also show
SW'lies, while NGP has a weak ridge over the North Sea and SW'lies for all.

Evolution to T+168
ECM shows high pressure building over Iberia. A trough crosses the UK on day
6, bringing strong westerlies for all. The westerlies ease slightly on day 7
as pressure rises to the south.
GFS brings westerlies and a weak ridge over the UK on day 6, followed by
strong SW'lies on day 7 as the ridge builds to the SE.

Looking further afield
Beyond T+168, ECM shows NW'lies on days 8 and 9 as a ridge moves eastwards.
By day 10 the ridge covers the UK with westerlies.
GFS brings SW'lies and WSW'lies over the UK on days 8 to 10, with complex
low pressure revolving around Iceland.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a "sine wave" pattern emerging, heralding the change to
zonality for the weekend and beyond.