We're expecting widespread plowable snow Wednesday, commencing late Wednesday afternoon and lasting into the night. This season, it almost feels strange to mention a moderate to high confidence forecast for snow by Wednesday evening's commute, but that's the situation now as a strong storm over Southern California runs the nation. As that storm pulls across the Great Lakes it will drag a swath of warmth and moisture northward into New England and the collision of warmth and moisture with preceding cool and dry air will result in snow. Though nature may still pull a trick with regard to precipitation type, I think it'll be very hard to avoid a burst of snow for most later Wednesday, coincident with the evening commute.
A few bullet points:
- Expect two rounds of precipitation. The first Wednesday late afternoon into Wednesday night, as the surge of warmth and moisture arrives. The second on Thursday.
- The map below is an early estimate of ROUND ONE snow - that is Wednesday PM. Thursday's snow is still too uncertain. (Technical point: the reason for uncertainty Thursday is a potential "center-jump" of the storm, where the energy will move so quickly that the storm redevelops offshore, which may mean New England gets bursts of snow with the energy passage, rather than a second shield of snow - too early to say for sure, but that's my guess)
- Plowable snow is expected for most Wednesday afternoon and evening
- Though temperatures will be marginal for rain or snow, and the immediate South Coast may well see rain due to an onshore wind, most New England communities are likely to see mostly snow, owing to very low dewpoints (measure of the amount of moisture in the air), which will mean the air will cool as precipitation moves in
Early snowfall estimate for ROUND ONE - Wednesday afternoon into Wednesday Night. Again, additional Thursday snow yet to be determined! Widespread 3"-6" - less farther northeast and also where some mixing is possible along South Coast/South Shore: