Possible Return to cold next week - Potentially Severe

M.T. Cranium wrote: »

Folks, use this mild spell and the open conditions (even when it turns a bit colder early next week, it won't be very wintry as such) to get yourselves well prepared, because I think a real blast of winter is coming back with a vengeance around the 16th or 17th, and here's what I just posted on another forum:

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I think the eventual outcome will be closer to GFS than ECM in the day 8 to 12 time frame, but taken together it shows the potential in this situation for a massive arctic outbreak with a cyclonic disturbance embedded. I would take that as the main theme and given the energy peak at 20-21 Dec, a plausible outcome would be for cold to sweep south, create a vast pool of sub-freezing air mass, then create a storm at the maritime boundary somewhere west of France that would try to move east along the southern boundary of the cold air mass at that time. Could spell snowstorm or even blizzard potential for the UK and Ireland around that time frame, and as for any push back of mild air afterwards, that's likely down to the GFS tendency to try to return to zonal default. The signal is so persistent and so strong (and so well-timed with the retrograde index peak on 20 Dec from my research) that I have to say, word to the wise, there could be a very disruptive period ahead from about Thursday 16th on, use these mild and open days while you have them especially if you're in a location or situation that is prone to travel disruptions.

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Just to give boards readers some extra thoughts on this, the models at day 8 and beyond can only be taken as general indicators. Some of the details especially the location and intensity of actual storm systems, often come into focus only by about day 4-5. This is why I try to blend my research with the model output in forecasting, because on a statistical basis, the research is actually more likely to verify in gross terms than the model output at day 8 and beyond. Now there's quite a difference in the ECM and GFS at present, but they share the common theme of massive retrogression (that being the westward shift of high pressure next week) and large-scale cold outflow from the arctic towards Europe. If I blend that general foundation and take some of the shaping of each model, then factor in my research data, I see every possibility of winter storm conditions developing some time during the period and most likely around 20-21 Dec but certainly within the larger time frame of 18-23 Dec. As to any milder push back around Christmas, that so far is only based on the inevitable tendency of the GFS to start returning to default values -- you can pretty much sense as a weather watcher that the massive cold outbreak on the 18z run is being slowly dissolved into some artificial zero-anomaly grid, nature wouldn't just bring south all that potent cold air and have it decay over a five day period, it's much more likely to lead to active frontal boundary dramatics of some kind, especially with the major energy peak so conveniently timed.

ro_chez wrote: »

df1985 wrote: »

when people say be prepared/stock up, what exactly are you referring to,the obvious things like food/heating oil etc or am i missing something. I know its probably a dumb question but first xmas at home this year where im "in charge" of the house, dont want to be stuck.

El Horseboxo wrote: »

Have a feeling this is another big hyped one with a lot of knowledgeable heads on board that just doesn't pan out as expected.

pauldry wrote: »

Just an idea...no not a charity .. but do you think if we all got our hairdryers plugged in around 17th December and stuck them out the window would the warm air turn the snow back to rain ? ....not forgetting to switch them on of course

Jake1 wrote: »

jebus, getting chugged on the boards now too .

I was in town today, I counted 17 different people who asked me for money for charity.

personally I think it should just remain a weather thread.

( awaits roars of Scrooge, boo hiss...) :P;)

maquiladora wrote: »

WolfeIRE wrote: »

area of low pressure centred over scotland would give us potentially a lot of snow tntn.