Here is a summary of the latest NWP output for noon on Thursday. Issued
0611z, 19/12/04.

The models continue to show a mobile picture. It now looks like Christmas
Eve will see colder air pushing southwards during the day, behind a trough
and this colder air should cover much of the UK by the end of Christmas Day.
It could well be cold enough over northern areas of the UK for some snow,
but it's still borderline for much of England and Wales. As ever, more runs
are needed.

ECMWF: http://64.246.48.81/pics/Recm1201.gif
A deep low lies to the north, bringing strong westerlies for all. A trough
moves SE'wards on Christmas Eve to bring NW'lies over Scotland and Northern
Ireland, with westerlies persisting elsewhere. By Christmas Day the winds
are NW'lies and WNW'lies for the UK.

MetO: http://www.wetterzentrale.de/pics/Rukm1201.html
The Met Office run shows a sub 940hPa low to the west of Norway, with a
trough across the UK bringing NE'lies and northerlies for Northern Ireland
and Scotland. Elsewhere, winds are westerlies, followed by much lighter
anticyclonic winds on Christmas Day as a weak ridge crosses the UK.

GFS: http://64.246.48.81/pics/Rtavn1201.gif
As with the previous two runs, a trough covers the UK on Christmas Eve to
bring westerlies for England and Wales, with NNW'lies or NW'lies elsewhere.
850hPa temperatures vary from -10C over northern Scotland to +2C over
Cornwall. Christmas Day sees a low over southern England, a trough over
northern Scotland and a weak ridge in between. The low moves away to the
east by Boxing Day, leaving the UK under NW'lies. Milder NW'lies cover the
UK on day 8 as a low moves SE'wards over NE Scotland, with a weak ridge and
westerlies on the chart for day 9. By day 10 the Azores High ridges over
Iberia, bringing mild westerlies across the UK.

GEM: http://www.meteocentre.com/models/glb00_120.html
A trough covers Scotland, bringing NE'lies there and westerlies elsewhere.
Another trough crosses the UK on Christmas Day, followed by yet another on
Boxing Day. By then, winds are NW'lies over Northern Ireland and westerly or
WSW'ly elsewhere.

GME/DWD:
http://www.wetter.com/home/img/sat/g...170000_120.gif
Strong westerlies cover the UK due to a trough to the north. Christmas Day
sees westerlies and SW'lies as the result of a secondary low west of
Scotland. The low moves ENE'wards on Boxing Day to bring NW'lies for all.

JMA: http://www.wetterzentrale.de/pics/Rjma1201.html
The UK lies under strong NW'lies with low pressure over southern Norway. The
winds become westerlies for all on Christmas Eve, followed by stronger
WNW'lies on Christmas Day. Boxing Day sees complex low pressure over and
west of southern Scandinavia, with westerlies and WNW'lies persisting over
the UK.

NOGAPS: http://129.13.102.67/wz/pics/ngp10.prp.120.europeg.gif
A low lies to the south of Norway, bringing northerlies for Scotland and
westerlies elsewhere. Christmas Eve sees westerlies and SW'lies as a trough
approaches from the west.

GM CPTEC: http://www.cptec.inpe.br/prevnum/Global126_sx6_Gl.shtml
The Brazilian run shows deep low to the north of Scandinavia, with strong to
gale force westerlies across the UK.

KMA: http://www.kma.go.kr/kma03/gif/g21nh_smsr_120.gif
The Korean run is very similar to the Brazilian run in that it shows strong
westerlies for all as the result of a low to the north of Scandinavia.