Our attention is now focused on the weekend, a Polar Vortex and a clipper system. The European model has been the lone sailor showing that this system tries to blow up south of Long Island and potentially bring some significant snows to New England. Even the Euro has been a bit fickle with this system however and has yet to provide details with any consistency. Personally I am having doubts about this potential storm. The "PV" can be a very overwhelming feature consisting of very strong winds at jet stream level which often act to guide East Coast systems out to sea before they attain any real strength. Nevertheless, the clipper itself, even without the support of Atlantic moisture, can deliver the mountain a few inches of snow Friday night. It will be a very cold weekend, one of the coldest of the season with well below zero wind chills Saturday and a few nights of well below zero actual temperatures through Monday.
We are going to lose the support of the AO in roughly a week and the pattern will transition into a more traditional La Nina looking set-up. A large ridge across the Gulf of Alaska, a trough and unsettled weather over much of the west, warm weather in the southeast U.S. and a big question mark for New England. Actually the question mark relates to what should be a significant weather system that arrives between the 15th and 17th of the month. The breakdown of the "negative AO" opens up the possibility for a non-snow event but its still "to be decided".