In message , Norman Lynagh
writes
Alan [Guildford] wrote:

On Thursday, 29 December 2016 14:58:52 UTC, N_Cook wrote:
On 29/12/2016 13:57, Alan [Guildford] wrote:
Obviously out in fantasy land but something to dream about


http://www.wetterzentrale.de/maps/GFSOPUK06_324_1.png



I assume the dot-chain isotherms there, are for 500HPa

Yes so cold upper air with 500mb-1000mb thickness circa 512dam for South East
England. The low would also bring significant dry snow for South East
England. Highly Unlikely but nevertheless interesting set of charts for
today's 6Z GFS at T+324

......but that run is an extreme cold outlier amongst the ensembles at 06z. To
take any notice of it would be very unwise.


Of course it would be unwise to take much notice. That said, the
ensemble mean is looking quite chilly from about the 6th January
onwards, with some other ensemble members being little warmer than the
operational.
--
John Hall
"One can certainly imagine the myriad of uses
for a hand-held iguana maker"
Hobbes (the tiger, not the philosopher!)