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zaax · **Today's model interpretation (6/08/09)**

Darren Prescott wrote:

Here is a summary of the NWP output for noon (GMT) on Wednesday.
Issued 0549z, 6th September 2008

The models are split today. ECM shows a trough crossing the UK during
the latter half of next week, with rain for all. GFS instead shows a
weak ridge by the end of the week, followed by a prolonged col.

Analysis and evolution to T+120 via GFS
http://85.214.49.20/pics/Rtavn001.png
Low pressure covers England and Wales, with NE'lies elsewhere. The
low moves eastwards tomorrow, with northerlies and NNW'lies as a
result. Monday sees the low move over the North Sea, with a col over
much of the UK. Southerlies and SSE'lies cover the UK on Tuesday as a
weak ridge moves over England.

T+120 synopsis
http://85.214.49.20/pics/Rtavn12014.png /
http://85.214.49.20/pics/Rtavn1201.png
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 ridge over England and Wales, with the jet heading
northwards over Scotland and Northern Ireland. Upstream there's a
trough, with a strong and zonal jet over the western Atlantic. There
are southerlies aloft at the 500hPa level, again with a trough to the
west. MetO shows a trough to the west too, while ECM has upper
SW'lies instead. GEM brings an upper col over the UK. At the surface
GFS shows southerlies for all with a deep low to the NW and a trough
to the west. MetO has a shallower low to the west, resulting in
SSE'lies. SSW'lies affect the UK with ECM, due to a low to the SW.
GEM has low pressure over northern Scotland, with light WSW'lies
elsewhere.

Evolution to T+168
Day 6 with ECM brings a deep low to the west, leading to strong to
gale force SSE'lies and southerlies. The low fills on day 7, with
lighter WSW'lies for all. A ridge covers the UK on day 6 with GFS,
leading to light winds. The ridge persists on day 7, although by then
strong SW'lies affect NW Scotland from a low to the NW.

Looking further afield
On day 8 with ECM the UK lies under a col. England and Wales remain
under a col on day 9, as a high to the north of Scandinavia blocks an
approaching low from the west. Southerlies start to affect Northern
Ireland and Scotland. On day 10 the high builds slightly towards the
UK, with light winds for all. SW'lies cover Scotland and Northern
Ireland on day 8 with GFS, while England and Wales lie under a col. A
col covers most areas on day 9 and on day 10 there's little change.

Ensemble analysis
(http://91.121.94.83/modeles/gens/gra...ext=1&y=141&ru
n=0&ville=Londres) The ensembles continue show a warmer spell next
week.

Would that be the remnants of HANNA ?

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