Friday, February 9, 2024

Need some northward shifting to turn Tuesday's system into a big snowfall for northern Vermont

We've had Colorado-type weather over the northern Vermont high country with chilly nights, warm afternoons, to go along with low wind and low dewpoints. The visibility and blue sky have been spectacular, but weather patterns are fluid, especially in New England and we are about to experience some changes. The clouds on Friday shouldn't limit visibility too much and the higher south southwest winds are expected to remain just above the surface which will help keep temperatures closer to 40 degrees during the afternoon instead of soaring to 50 and beyond. Winds are expected to pick up a little on Saturday which will help boost temperatures into the 40's, but models aren't suggesting a big mix down of record breaking warmth or an intense version of snow eating winds; instead, a cloudy mild day is followed by a short-lived burst of rain amounting to less than a tenth of an inch. By Sunday morning, any rain will become light snow as temperatures fall back toward the freezing mark and hold there through much of the day. 

We will be understandably hungry for some new snow following Saturday's warmth which makes the weather system on Tuesday of vital importance. I promised we would have more clarity on this storm by now and I will try and provide as much as I can.  Low pressure will move quickly out of east Texas on Sunday and continue to intensify as it approaches the Virginia tidewater area Monday evening. We remain very much in play for this storm but we need northward shifting if we are to receive any material snowfall. The Euro ensembles which had been reliably consistent, showing some impact for most of the state have shifted southward and are now contributing to a model consensus that would suggest a minimal impact for the MRV. We've seen this movie many times and I don't see mechanism present to slam the door on a northward shift, yet I also want to convey what the model data is illustrating now - a 1-4 inch event during the day Tuesday. Once this strengthening storm exits, a colder temperature regime will better establish itself and it certainly appears as if Tuesday could be the start of a very extended stretch of sub-freezing temperatures. More on that in a paragraph below. For the rest of next week, there's a chance some moisture could wrap in from the north underneath all the downstream blocking and enhance as it it encounters the mountains. Worth keeping an eye on that and a potential clipper system ushering in a reinforcing and stronger version of colder air for the weekend of the 17th and 18th. The southern branch remains of the jet is also indicated to remain active and could always get involved, but the prevailing storm track, for the time being does appear south of us between Valentine's Day and Sunday February 18th. 

Forecasters have backed away from the extreme cold scenarios that were indicated for the back half of February. Ensembles never really conclusively showed such an outcome, but that didn't stop the hype. That said, the weather pattern continues to look wintry and supportive of more snowfall at least through Sunday February 26th and perhaps beyond. The coldest period occurs around the President's Day holiday weekend and I do expect at least a minimal amount of snowfall in this time frame. After that it will just be a question of if and win we can get one of these big southern streaming systems to evolve into a big east coast snow producer. The odds are pretty good one will given the availability of some cold air and the downstream blocking support being provided by the -NAO.

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