Winter 2011/2012 Pattern Discussion

Homemommy wrote:I saw on the news this morning that Chicago is having the warmest winter in 80 years. A bunch of states broke like 40 records this week.

WESTERN ARCTIC COAST-
INCLUDING...WAINWRIGHT...ATQASUK...POINT LAY...CAPE LISBURNE
1153 AM AKST THU FEB 2 2012

...WIND CHILL WARNING REMAINS IN EFFECT UNTIL 6 AM AKST FRIDAY...

A WIND CHILL WARNING REMAINS IN EFFECT UNTIL 6 AM AKST FRIDAY.

* WIND CHILL VALUES...AS LOW AS 80 BELOW.

Toot wrote:The euro and gfs are both showing a trough in the east at day 10 which is in good agreement with their ensembles

snowdog wrote:
12z Euro Ens. In the west Pac you can see the flow being squeezed between the 588 and 498 contours which results in a screaming north pac jet which leads to zonal flow across the US.

this run is different from GFS in how it handles the western ridge, but its a big change so don't know if its correct with that, which has a huge impact downstream. The GFS wanted to lurch the western ridge north above Alaska and cutoff, so that would be more like what we've been trhough, with the cold air not really able to push down into the eastern US, but the ECMWF holds a major tall, elongated ridge out west, perfect position to force the cold to drop in.
The first close call is what it does with the western wave as it drops down toward Texas around day 5, with cold air and high pressure in the Ohio Valley, pressing south...could be cad there, as well as cold enough for snow in northern Ark, Tn, maybe TN (atleast before a changeover, then changing back over). Meanwhile that races east but by then another s/w is dropping due south with another 1040 high, associated with very cold air, and that makes good progress through the eastern half all the way through the Southeast. The Atlantic ridge could work northwest, thanks to a fujiwara effect of the deep cold vortex around southern Canada and the lakes, and how the western Ridge holds in place, without really cutting off too far north.
By day 10, we have a very good, winter time look, with supressed flow. Don't know if its right, but the models could be reacting to the strong -AO lately, and with Europe warming up around this time, the cold gets redistributed and a neg NAO isn't far off. Again all this could be way off since modeling has been hard this season. We'll have to wait and see (and hope) that it works out similar to this. The change begins fairly soon, around day 5 but the way the pieces fall in place will determine how much cold eventually works south and east and if we end up with a supressed storm track and split flow and -NAO.

snowdog wrote:Do you have a good model verification link?

Stovepipe wrote:Hour 348 00z GFS = MOTHER OF GOD

Folks been waiting on atleast fantasy maps, the GFS delivers. It has beautiful blocking, practically double blocking in the perfect spots on the last few panels. It's something to see if it holds on to it, but obviously so far out chances are it's not exact. I will say the overall evolution of the hemispheric flow makes a lot of sense. Usually an extreme solution in Alaska, then Europe, is followed by a Major High Plains event, a Northeast coast event, then a deep south event. Most of the evolutions of big snows I've studied that had blocking in Winters in Alaska, followed that pattern. So we'll see.