Happy Winter Solstice !! Scrooge still seems intent on messing with our holiday week, yet again, but at least we have a bit of winter weather to talk about in the short term. Two disturbances, one on Thursday and one on Christmas Eve appear capable of bringing light accumulations of snow to the Green Mountains. Thursday's system is an Alberta Clipper and will spread snow into Vermont by daybreak. Snow should continue through much of the day and though it is not expected to be particularly heavy, it will be of the fluffier variety and should accumulate 2-4 inches by Thursday evening. The Christmas Eve system looks particularly innocuous on the weather map but models have converged on the involvement of a little bit of subtropical energy and moisture. There are parts of our state that are perilously close to seeing mixed precipitation out of this, and low lying valley locations might indeed see some mixed rain and snow or very wet snow as temperatures on Christmas Eve rise into the middle 30's. Across the high country of central and northern Vermont, precipitation should stay snow and another 1-3 inches is possible, most of it falling during the ski day.
Arctic air will sneak in the side entrance following our light accumulation of snow on Christmas Eve. The airmass will keep Vermont and the rest of interior New England wintry on Christmas Day while the rest of eastern North America sees much milder weather. Bad teleconnections, much of it discussed in previous posts are the culprit for the push toward warmth but from the perspective of actual weather maps, it will be a well organized storm system that will spin its way into the northern plains on Sunday. This storm will advance well into Ontario and Quebec on Monday and will bring milder air and rain to New England. Indications are that temperatures won't be excessive in a relative sense but 40 degrees and rain is possible either late on Monday or early Tuesday. Temperatures briefly return to normal during the middle of the week but another push of milder air will threaten to bring another dicey weather situation to New England ski country Thursday or Friday. Interestingly, ensembles have trended toward a "less warm" overall scenario in this period leaving open the possibility of frozen precipitation. Unfortunately, rain is also a possibility. We will need some additional time to sort through all that.
New Years weekend does appear colder based on data released late yesterday and early this morning. Though we will have yet to attain any categorical support of the some of the teleconnection indices such as the PNA or EPO, a large, albeit temporary, east coast upper trough is expected to amplify and bring a return of wintry temperatures and snow to the region on December 31st, Jan 1 and Jan 2. It's too early to speculate how much snow might fall or where it might come from. We also won't be completely out of the woods as far as seeing additional pushes of milder air in the first week of 2017.