The precipitation map from the GFS for next Saturday evening looks hauntingly familiar to the one from last week, which did not pan out in a snow event, except for the favored lake-effect areas.
But the key to this one would be colder temperatures, frozen ground in many areas, and most importantly a long duration -- the model shows snow over most of Pennsylvania for more than 60 hours. The only other model which runs in that time frame is the DGEX, which runs from GFS conditions at 84 hours. It is much higher resolution and shows the event as only happening in the higher elevations of the Appalachians Saturday:
It's hard to tell if this is just the difference in resolution talking but it seems that, unlike the GFS, the DGEX never really shows snow outside of the higher mountains.
AccuWeather.com Professional's Joe Bastardi (PRO) is also hyped, predicting a 28.80" Hg low pressure Saturday in the Gulf of Maine (the equivalent of a Category 2 Hurricane according to Saffir Simpson [Wikipedia]). He also says:
"Heavy to excessive rainfalls from Texas to the mid-Atlantic, with heavy precip that could very well turn to snow from the Upper Midwest through the Great Lakes and interior Northeast, strong winds that can gust over 60 mph in the cold part of the storm driving flurries and squalls as far south as we will see them go now, perhaps even further."
The models continue to show a very deep low pressure system approaching the United Kingdom & Ireland near Christmas Day.
The historic Mideast snowstorm and upcoming U.K. Christmas storm observed through computer forecast model images.
A pair of mesoscale vortexes formed over Lake Superior yesterday. I pulled up 3-D radar data just before the storms made "landfall."
A major snowstorm is headed to the Northeast U.S. -- including AccuWeather HQ.
The lake-effect snow machine is cranking out some incredible amounts during the first 24 hours of this major outbreak. Here are top amounts, webcams and 3D radars:
The coldest air of the season plagued Montana and surrounding Canada last night, knocking temperatures well into the -40s F, with wind chills in the -60s!