"Scott Whitehead" wrote in message
...
On Tue, 3 Jan 2006 10:07:10 -0000, "Will Hand"
wrote:


================================================= ===================
This posting expresses the personal view and opinions of the author.
Something which everyone on this planet should be able to do.
================================================= ===================

Don't normally say too much in between my weekly forecasts but in light of
the
developing very cold and prolonged scenario I thought I'd say a few things.
Looking at the last few runs of all the models I would say that the
ingredients
are coming into place for a possible major very cold spell. Confidence in
this
is now 40% at Haytor (rising from 10% last Friday). Very cold air pushing
down
from the Arctic (sub 492 DAM) to the east of the Russian anticyclone will
help
persistence as will the continued feed of low potential vorticity tropical
air
from the south to the west. Not quite a classic omega pattern yet but could
well
end up as one. Air close to the surface will become very cold as it stagnates
due to radiation balance at this time of year so 850 hPa temperatures of -5
to -10 deg C are easily attainable. Operational GFS is showing outbreaks of
light snow over the UK in the developing easterly this is consistent and to
be
expected in a slightly unstable situation despite high pressure. Of course
the
orientation and resting place of the anticyclone is key as always as to
locations that get snow, all of southern Britain is at risk of at least some
light snow. A wind either due east or south of east could give Devon and
Cornwall some persistent and heavier snowfall, but that detail is elusive at
present. Clearly one has to go for a lot of dry cold weather too in western
areas and I think eventually we will see fronts pushing in from the west, but
these are likely to struggle more against a more intense block than last time
due to:

1. Radiation balanace
2. Cold air advection from the north to the east of the high
3. Orientation and lack of a strong westerly flow coming out if the States
unlike last time

This one should be watched because we could be facing (40% chance) a month of
very cold weather albeit on the dry side of normal.

Will.

Will,

Would you see the influence of this possibly huge developing
anticyclone to stretch beyond the European Alps - any drier than
normal spell would have severe consequences on the ski industry.

While the north, east and western resorts had good early season
snowfalls due to the prevailing wind, resorts around to the south have
been struggling with the absence of any meaningful snow since the
beginning of December.

Obviously the temeratures have been at times very cold and
sufficiently low enough for snowmaking - but this has only been enough
to keep skiiers who stick to the pistes happy enough.

Thanks,

Scott


Scott, depends where the block finally ends up. ATM it doesn't look too good for
the Alps as regards fresh snowfall.

Will.
--