Now looking more progressive.

Will
--

"Eskimo Will" wrote in message
...
Now looking more progressive.

Awesome run. 492DAM into Iceland on Christmas Day and the Russian high
retreats big time to be replaced by a Greenland high. Could see the return
of "light icing" in the shipping forecasts for Iceland. Also the
introduction of a colder PM flow just might, just give dartmoor a flake of
sleety snow in a heavy shower on Christmas Day.

However, ....... it is just one run, but so different to yesterday's 12Z run
which retrogressed the Russian high for a while.
Fascinating!

PS BTW Nick if this progressive story comes off then you will have a
brighter holiday with some sunshine in nice clean polar air.

Will
--

On Dec 19, 4:27*pm, "Eskimo Will" wrote:
"Eskimo Will" wrote in message

...

Now looking more progressive.

Awesome run. 492DAM into Iceland on Christmas Day and the Russian high
retreats big time to be replaced by a Greenland high. Could see the return
of "light icing" in the shipping forecasts for Iceland. Also the
introduction of a colder PM flow just might, just give dartmoor a flake of
sleety snow in a heavy shower on Christmas Day.

However, ....... it is just one run, but so different to yesterday's 12Z run
which retrogressed the Russian high for a while.
Fascinating!

PS BTW Nick if this progressive story comes off then you will have a
brighter holiday with some sunshine in nice clean polar air.

Will
--

Nice! :-) Hope it does come off.

Nick

On Wednesday, December 19, 2012 4:07:20 PM UTC, wrote:
Now looking more progressive.



Will

--

It doesn't look hugely different to the 06 or 00 UTC runs to me, to be honest - zonality ramming in. A bit chillier 25th to 27th Dec.

Stephen.

But, yes, very different to yesterday's 12UTC... because that was an enormous outlier! It was interesting that for Germany, for example, nearly all the GFS ensemble members in the 00UTC GFS today were below even the coldest members of the 12UTC GFS ensembles yesterday. You don't often see such a huge change in ensembles at such short lead time. ECMWF has been somewhat steadier.

Stephen.

On Wednesday, December 19, 2012 5:16:41 PM UTC, Stephen Davenport wrote:
But, yes, very different to yesterday's 12UTC... because that was an enormous outlier! It was interesting that for Germany, for example, nearly all the GFS ensemble members in the 00UTC GFS today were below even the coldest members of the 12UTC GFS ensembles yesterday. You don't often see such a huge change in ensembles at such short lead time. ECMWF has been somewhat steadier.



Stephen.

==========

Er, I meant 12UTC ensembles yesterday were way colder than the 00UTC previously...

Sorry.

Stephen.

"Stephen Davenport" wrote in message
...
On Wednesday, December 19, 2012 4:07:20 PM UTC,
wrote:
Now looking more progressive.



Will

--

It doesn't look hugely different to the 06 or 00 UTC runs to me, to be
honest - zonality ramming in. A bit chillier 25th to 27th Dec.


I have to disagree. The Russian high collapses far faster allowing the upper
trough axis to be further east. The cold advection off the Arctic east of
Greenland consequently digs further south rather than heading WSW as in
previous runs. What I hadn't remembered was that it ties in with the ECM 00Z
ensembles quite well.

Will
--

On Wednesday, December 19, 2012 5:27:29 PM UTC,
I have to disagree. The Russian high collapses far faster allowing the upper

trough axis to be further east.

===========

This much is true, and it's particularly reflected in an absence of cold outbreak across Germany early next week. But broadly aside from that (and I think it may be collapsing the Russian High too quickly on this op run) it is progressive next week as became before, and I'm not too sure that it has huge import for overall UK conditions. At least, not much different from what I've bneen forecasting! Maybe I'm thinking in longer range. On another thread, mind you, note that I've suggested eastwards movement of the trough axis.

Stephen.

In article ,
Eskimo Will writes:

"Eskimo Will" wrote in message
...
Now looking more progressive.

Awesome run. 492DAM into Iceland on Christmas Day and the
Russian high retreats big time to be replaced by a Greenland high.
Could see the return of "light icing" in the shipping forecasts for
Iceland. Also the introduction of a colder PM flow just might, just
give dartmoor a flake of sleety snow in a heavy shower on
Christmas Day.

However, ....... it is just one run, but so different to yesterday's 12Z
run which retrogressed the Russian high for a while.
Fascinating!

PS BTW Nick if this progressive story comes off then you will have
a brighter holiday with some sunshine in nice clean polar air.

Will
--


The 12Z GFS ensemble 850mb temperature plot is now out. For 51N 2W
(which I suppose would equate to somewhere in the region of Bristol), a
very mild spell leading up to Christmas is followed by a sharp fall in
temperature on Christmas day. After that the spaghetti spreads out
widely, but with the mean close to or just below the long-term average
for the rest of the run. The operational run is one of the milder
ensemble members from about the 28th onwards. So the main features of
the plot haven't altered that much from the 00Z, though the mean
solution is slightly colder.
--
John Hall

"Whenever people agree with me I always feel I must be wrong."
Oscar Wilde

What's with the Iberian High? Until heights drop there, I can't see much in the way of cold reaching southern England.