Here is a summary of the NWP output for noon on Saturday.
Issued 0530, New Year's Day 2008
**Happy New Year everyone!**
The weekend will see mild, wet and windy weather spreading across the UK as
a powerful Atlantic jet affects us. GFS is very progressive, with a zonal
flow setting in, while ECM keeps the high to the NE around for longer. Both
outcomes lead to plenty of wind and rain with generally mild temperatures,
however.
Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
Southerlies and SSE'lies cover the UK, with a low to the WSW and high
pressure building to the NE. Tomorrow SE'lies affect all areas as the high
to the NE builds and the trough to the SW disrupts. Thursday sees a strong
and cold easterly flow across the UK, with snow in places. By Friday the
winds ease over England and Wales and back ENE'ly over Scotland and Northern
Ireland, as the remnants of an upper low move over 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://www.meteociel.fr/modeles/nogapse_cartes.php
The jetstream chart shows a strong jet across the North Atlantic, the UK and
Scandinavia. At the 500hPa level an upper ridge stretches from the Azores to
Russia, having absorbed the Russian high. The Met Office run shows upper
WSW'lies, again with a large high to the south. ECM shows something slightly
different, with the upper low near Iceland further south and west. There are
upper SW'lies over the UK and lower heights than with the other runs. NGP
has upper SW'lies too, with a low to the north, while GEM shows an upper low
over Scotland.
At the surface GFS has strong SW'lies with complex low pressure to the north
and a ridge to the south. MetO brings SW'lies too, with a deep low to the
north. SW'lies feature on ECM too, as is the case with NGP and GEM. The
latter shows SE'lies for Scotland, with low pressure over SW Scotland.
Evolution to T+168
ECM shows WSW'lies on day 6 as low pressure persists to the NW. A secondary
low deepens rapidly as it moves ENE'wards over England on day 7, with
SW'lies persisting over Northern Ireland and Scotland.
GFS brings mild SSW'lies over much of the UK on day 6 due to a low to the
west. The low moves swiftly NE'wards on day 7, with SW'lies across the UK.
Looking further afield
ECM shows low pressure to the NW on days 8 to 10, with SW'lies backing
southerly on day 9. Day 10 sees a trough move in from the west, with SW'lies
for Northern Ireland and strong to gale force SSE'lies elsewhere.
GFS brings SSW'lies on day 8 as pressure builds to the east. The winds
become southerlies on day 9 with low pressure deepening to the NW. By day 10
a trough approaches from the west, leading to strong southerlies across the
UK.
Ensemble analysis
(
http://91.121.94.83/modeles/gens/gra...ille=Lon dres)
The ensembles continue to show a mild and wet spell approaching for the
weekend.