Here is a summary of the NWP output for noon on Thursday.
Issued 0543, 14th March 2010

The models are split today. They agree on a general SW'ly flow over the UK
by the end of the week, with mild weather for most and rain especially in
the north and west. Thereafter the ECM keeps the zonal theme going while GFS
moves the jet south and allows a colder easterly to become established.

Analysis and evolution to T+120 via GFS
NW'lies cover the UK, with a high to the SW. There's little change tomorrow
but on Tuesday a ridge moves eastwards, with high pressure over England and
Wales. Further north winds are westerlies, followed by southerlies for all
on Wednesday as the ridge moves away to the east.

T+120 synopsis
http://91.121.93.17/pics/Rtavn12015.png /
http://91.121.93.17/pics/Rtavn1201.png
http://91.121.93.17/pics/Rukm1201.gif
http://91.121.93.17/pics/Recm1201.gif /
http://www.meteociel.fr/modeles/nogapse_cartes.php
The jetstream chart shows a weak westerly flow over the UK, with a strong,
zonal and southerly-tracking jet over the Atlantic. At the 500hPa level
there's a SW'ly flow, with a trough to the SW. ECM has SW'lies aloft with a
ridge to the east, as is the case with MetO and GEM. JMA brings an upper
ridge and westerlies aloft for the UK.
At the surface, GFS brings southerlies with a low west of Ireland.
Southerlies also appear on the ECM chart, with a deeper low to the WNW. MetO
has SSW'lies and a low to the NW, while GEM brings southerlies due to a
trough to the west. JMA shows southerlies and a low to the WNW.

Evolution to T+168
ECM shows a deep low to the west and southerlies on day 6. Day 7 sees
WSW'lies with a low to the north.
GFS brings a trough over England and Wales on day 6, with ESE'lies. Further
north there are easterlies, with a high west of Norway. On day 7 low
pressure remains to the SW, leading to strengthening ENE'lies across the UK.

Looking further afield
ECM shows SW'lies on day 8 with a low to the north, followed by westerlies
and SW'lies on day 9 due to a high to the south. The high builds to the east
on day 10, leading to southerlies.
GFS has strong to gale force easterlies and ENE'lies on day 9 with a high to
the north. The high moves SE'wards on day 9 with the winds veering SE'ly as
a result. There's little change on day 10.

Ensemble analysis
(http://91.121.94.83/modeles/gens/gra...ille=Lond res)
The GEFS shows a warmer blip later in the week before temperatures fall back
closer to average.

ECM ensembles
http://www.meteogroup.co.uk/meteo/ep...tt6-london.gif
The ECM ensembles show the operational was one of the mildest options.