Storm to bring 15-25 inches Friday and Saturday to areas above 1500 feet with another possible storm lurking late next week

With each new piece of data, I've become more impressed with our upcoming event. Just a perfect type of storm to get the season started. As I mentioned yesterday, this isn't a "bombs away" situation or a storm capable of reaching any kind of historical strength as far as nor'easters go, but the weather pattern has created an ideal set of circumstances for this and it reminds me a little of the setup we had prior to getting clobbered with 4 feet of snow in late February of 2010. 

We continue to be working with an airmass that wasn't especially cold to begin with and has gradually become rather stale through the week. This allowed temperatures over valley locations Thursday to approach 40 degrees. It's a good thing our coastal low is establishing itself nicely Thursday and will track along the southern New England coastline because an inland runner would flood the region with warmth with little resistance. Fortunately, no inland runner is expected and we have a healthy, slow moving plume of moisture which should bring snowfall to the region by daybreak Friday. What is particularly impressive is the deep moist layer of southeasterly fetch or flow of air, which when rammed against the spine of the Berkshires and Green Mountains, enhance snowfall rates and bring some very impressive snowfall totals above 1500 feet. The warmth will make the snow consistency wet over valley locations and if you reside in a western shadow of a mountain range, you are in a big screw zone. Over the years, I've seen some wild snow shadows in these aforementioned regions and I think this is a really amplified case where areas just west of the big Green Mountain spine (thinking of you Middlebury, Bristol, Hinesburg and Underhill), will see limited gloppy snow and mild above freezing temperatures. Fortunately, most of us don't make turns in these areas (though some of you might) and if you stay above 2000 feet the results will be very good and considerably more powdery. The best part of this event is the extended stretch of time this pivoting area of moisture will sit over our area. This is just outstanding and should allow moderate to heavy snowfall to continue well into Saturday. It's this facet of the storm which will allow accumulations to reach 15-25 inches over the high country with a gloppier 10 inch snow expected in the valley and less in areas west of the Green Mountains. Folks always ask me about wind and though this is not an especially strong storm, it does have a healthy and deep easterly gradient as I mentioned. This means winds will be substantial Friday but slacken a bit Saturday while shifting 180 degrees and becoming westerly.

Sunday appears drier and a little cooler with temperatures hovering in the 20's in the mountains and near 30 in the valleys. As indicated in a prior post, some limited moisture should be able to return to northern Vermont in the form of some snow showers either late on Sunday, Sunday night or Monday though this has gradually appeared less impressive as our Saturday snow totals appear more impressive. The early part of next week then appears somewhat tranquil even as a motherload of arctic air invades western Canada and the pattern prepares to amplify for fireworks late in the week. 

I make no guarantees regarding the potential event on December 22-23. It can be very difficult for models to nail down weather events when the polar jet starts to get involved. It just creates a more chaotic environment and a difficult one to predict with small simulation errors amplifying into larger ones exponentially. That said, ensembles are showing an outstanding signal, 8 days out, for a major nor'easter with this one producing heavy snow, wind and featuring much colder temperatures both during and in the wake of storm. This event could end up out over the ocean and it was even indicated at one point to be an inland runner a few days ago (I highly doubt it at this point), but at the very least it provides an additional opportunity for snowfall prior to Christmas. Speaking of that holiday, it looks both windy and frigid most of the weekend and I will underscore the wind part because I don't think temperatures, though cold (single numbers and teens), will shatter any records. The cold air is expected to linger through the holiday week and I expect another chance at snowfall as the pattern softens and the arctic air either retreats or moderates. I actually expect an additional surge of cold prior to New Years over New England but the pattern overall over eastern North America is indicated to soften. There are hints at a strengthening Pacific Jet around the start of 2023, but I don't consider this a threat to holiday skiing in Vermont.