It was yet another holiday period littered with failures for snow lovers in Vermont. Winter did make a return on Sunday and we got a bit of snow for our troubles but it was another decided under-performance and it's on to January and the center cut portion of our cold season. And fortunately, we will have some cold to go with our January this go round. It won't measure out as historic but I going to project it will best last year's effort which came in at 2 above average. Last year's version of January was notable for the sustained stretch of sub-freezing temperatures we were able to maintain throughout the month. It would certainly be nice match that effort (more unlikely without -AO help) but more importantly we need the snowfall.
Though many of the warm water feedbacks I often discuss have been working against us this past month and certainly may have been critical in turning the recent holiday week to mush, the involvement of arctic cold is the ingredient likely to spice up the weather map in our favor. The coastal waters along the eastern seaboard are 3-6 degrees above average and this creates a tinderbox-like environment for big east coast storms when arctic chill is added to the mix. Storms need baroclinicity, or a broad region where cold dry air clashes with warm moist ocean air. The New England coastline has always been a geographically pristine area for such activity and our explosive winter storms have become famous enough to earn the region specific term of nor'easter as a result. In the case of this year, the extra few degrees of relative ocean warmth could create some rather special magic and some of this has already started with a strengthening storm to our south that is expected to deliver portions of the Mid-Atlantic with a fierce bout of snow on very short notice. I am hopeful that this trend continues as we progress toward the later part of this week and a potential storm that could lift us away from the unfortunate morass we found ourselves in over the holiday.
In the meantime, our sunshine finally makes a return Monday as promised. The east coast storm will keep most of the clouds and snowfall well to our south and this means crisp, cold, sunshine for much of the day followed by a cold near zero Monday night. Sunshine may give way to some clouds on Tuesday but it will be another quiet and very average day in northern Vermont. Southwest winds are likely to push temperatures past the freezing mark in valley locations Wednesday but the big Chukchi Sea block is forcing the jet stream to work and will allow large amounts of polar energy to move quickly south and east. Taken in the aggregate, the potential storm which is expected to take shape in the Tennessee Valley Thursday before exploding along the Mid-Atlantic coast during the evening has shifted a bit to the south and east. Two of the three major ensembles packages have consistently showed a decent hit for much of interior New England with the holdout being the American GFS which has been in and out of this party all along. Given the delicate nature of any situation involving an amplifying polar jet stream, there's actually a decent amount of support for a hit over much of interior New England though the storm will be fast moving and is not expected to get caught up in the maritimes for any period of time. The extra bit of relative warmth in the coastal Atlantic is a big benefit for Vermont in this setup and it certainly keeps the door open for a stronger storm and the famous northward shift that models often undergo late in the game. The timing of all this appears to be Thursday night into Friday with flurries and snow showers continuing into Friday night. If I could pick an over/under right now on accumulation I would say 6 inches with equal chances of besting or underperforming that number prior to the weekend of the 8th/9th.
Garden variety January chill can be expected for the weekend with blustery conditions persisting into early Saturday followed by a calmer day Sunday. The polar jet will retreat into eastern Canada early next week and is expected to deliver New England another and stronger dose of arctic air by the 11th or 12th of the month but there is some concern that a surge of milder temperatures around the 10th could threaten interior New England with a dose of above-freezing temperatures and mixed precipitation. There are no indications of a major rain event but I would categorize this as a slight risk. After that, we should get some help from the PNA and a Pacific jet that is at least somewhat cooperative. Not a bad outlook overall but it would feel a lot better with some results in the bag and they have proved very elusive so far this season.
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