Here is a summary of the NWP output for 12z on Tuesday.
Issued 0535z, 30th March 2007.

The models continue to show high pressure and largely dry weather for the UK
for the latter half of the working week. There's disagreement about the
track of the high though and at the moment the odds slightly favour a warm
outlook, but there remains a significant chance of a brief cooler interlude.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
http://85.214.49.20/pics/avnpanel1.gif
Low pressure covers the English Channel, leading to a mixture of northerlies
and NE'lies over the UK. Tomorrow the winds become NE'lies for all as
pressure builds to the NW. The high continues to build on Sunday and by
Monday it covers Scotland and Northern Ireland; elsewhere winds are
ENE'lies.

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://www.meteociel.fr/modeles/nogapse_cartes.php
The jetstream chart shows the UK under a large ridge, with a strong jet to
the north and NE. At the 500hPa level a large high covers Scotland, while
ECM has the high further west. MetO is between the two, with a less strong
upper high to the NW. NGP has an upper high to the west instead while GEM is
similar to ECM and has the high to the WNW instead.
At the surface GFS brings light winds for all with high pressure atop the
UK. It's further to the west with ECM, leading to northerlies and NE'lies
for most. MetO is very similar, albeit with a slightly weaker high. NGP
brings a Greenland High ridging strongly southwards, with NW'lies. Finally
GEM brings a ridge over Scotland and Northern Ireland with ENE'lies
elsewhere.

Evolution to T+168
ECM shows the high declining and moving NE'wards, delivering a potent
northerly blast to Scandinavia. Over the UK winds are less cold northerlies
and NNW'lies.
GFS keeps high pressure over the UK on day 6 with further light winds for
all. On day 7 the high declines, leading to easterlies for most.

Looking further afield
ECM brings light winds and a ridge on day 8, followed by light westerlies
and NW'lies on day 9 as low pressure deepens to the NNE. The low deepens
rapidly on day 10, leading to gusty NW'lies across the UK.
GFS shows a ridge over the UK on day 8, followed by further light winds for
England and Wales on day 9. By then SW'lies and SSW'lies affect Scotland and
Northern Ireland, with low pressure to the WNW. On day 10 Northern Ireland
lies under a col, while Scotland is still affected by SW'lies. England and
Wales lie under ESE'lies from a high over the North Sea.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles show a 50/50 split for northern areas next week with half
staying warm and the other half showing a cold plunge. Further south it's a
66/34 split in favour of warm weather.