Darren Prescott wrote:
Here is a summary of the NWP output for 12z on Wednesday.
Issued 0601z, 13th January 2007.

The outlook is still unsettled, with all areas seeing wind and rain in the
latter half of the working week. By the end of the weekend it's likely a
high will move swiftly in from the west, bringing a couple of colder days.

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 mixture of westerlies and WSW'lies associated with a weak ridge cover the
UK. A trough will move across the UK and by tomorrow it'll lie over the
North Sea, leaving westerlies across the UK. Monday sees SW'lies for all
with a new trough to the west and a high over central and eastern Europe. By
Tuesday the trough fills as it crosses Ireland, leaving the UK under a
mixture of WSW'lies and SW'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://85.214.49.20/pics/Rngp1201.gif
The jetstream chart shows a a very strong, very zonal flow across the North
Atlantic. The core of the jet (off Newfoundland) approaches 200kts, but it's
around half that strength as it crosses the UK. At the 500hPa level the
pattern's equally flat over the North Atlantic, with the UK lying under a
SW'ly gradient. MetO and ECM also show a SW'ly gradient, with ECM having
lower heights for the UK. NGP and GEM are similar to the major runs, while
JMA has an upper low closer to the NW and an upper trough over the UK.
At the surface GFS brings southerlies for most with a weak ridge over
England. MetO has a deep low west of Scotland, bringing southerlies to
Scotland and SW'ly gales elsewhere. ECM also has a low to the NW, this time
with WSW'lies for all. NGP is similar to ECM, as is GEM, while JMA has a
trough over the UK. Ahead of the trough winds are strong southerlies, with
less strong WSW'lies following behind.

Evolution to T+168
ECM shows low pressure moving swiftly ENE'wards over the UK on day 6, with
westerly gales for England and Wales. Northern Ireland lies under lighter
NW'lies, with moderate NE'lies for Scotland. By day 7 a weak ridge covers
the UK with WSW'lies.
GFS brings a weak ridge over the North Sea at T+144, leading to a mixture of
WSW'lies and SW'lies for the UK. By day 7 complex low pressure lies to the
ENE and NNW, with a mixture of westerly and NW'ly gales for the UK.

Looking further afield
Beyond T+168, ECM shows westerlies for days 8 and 9, with low pressure
slowly transferring eastwards to the north. By day 10 a trough moves
SE'wards over the UK, with westerlies in advance and NW'lies following
behind.
GFS shows a trough crossing the UK on day 8. Ahead of the trough winds are
strong westerlies, with strong to gale force NW'lies following behind.
Lighter NW'lies cover the UK on day 9 as a ridge moves eastwards, followed
by westerlies and SW'lies on day 10 as a trough moves eastwards, bringing
much milder air back over the UK.

Ensemble analysis
(http://expert.weatheronline.co.uk/da...ia/ensdia.html - last
night's 18z)
The ensembles still show a "sine wave" mobile setup, but there are also
still signs of a colder interlude next Sunday for a couple of days.

What about today's:

South Coast Tropical Seas.
Ice Storm in USA
Aberdeen 15.0°c today
Steep temperature gradient near newfoundland...
+4 to -4
Breezy in Lerwick
fohn effect Leeds

Saturday's child was an 8.2
So Sunday's child is bright and blue
Monday's child has lots of Lows the blocking Highs are sure to go.
Tuesday's child has double Lows and again the Highs are blocking those
So Wednesday's child is full of woe,
And Thursday's child is moving slow,
Friday's child hosts another phase.
I bet it's going to be one of those days!,