A clipper-like system brought more snow to far northern New York, eastern Ontario, and southern Quebec today, where this winter is now so far the snowiest in many years. Meanwhile, farther south, it warmed up and little snow fell, and the snow drought continues, albeit less so than earlier in January. Behind it, the coldest air since Christmas will follow, though it is still only modified arctic air. A very weak system tracking slightly farther south will bring up to 2” (5 cm) of snow to the region tomorrow and tomorrow night.
As the polar vortex settles over Hudson Bay on Friday, an extremely cold air mass will charge southward into Northern New England directly out of Quebec. Unlike the Christmas cold air outbreak, in which the cold air came from the southwest and was modified by the Great Lakes and a long mid-latitude passage, this cold air mass will be unmodified by the Great Lakes and take the shortest path possible into our region, all over a deep snowpack, allowing for little modification. Temperatures could fall to -22F (-30C) where the cold high pressure happens to crest overnight, most likely Friday night, especially northwest of the Appalachians. Downslope warming and stronger winds will preclude temperatures being as cold southeast of the Appalachians.
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| Source: TropicalTidbits |
The polar vortex will also end the stormy pattern, which had earlier been expected to persist through early February. The trough will take aim at eastern Canada and although it will be intense, it will not dig very far south. It will also move too far east to pick up or phase with any moisture-laden storm coming out of the Gulf of Mexico or western Atlantic, and instead suppress the storminess to the south. Some snow showers and squalls are likely along and just ahead of the strong cold front that will bring the extremely cold air mass, but no major storm will occur. As such, the snow drought will likely continue south of the U.S./Canada border.
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| Source: TropicalTidbits |
With no blocking mechanism, the extremely cold air will be short-lived. By early the following week, the arctic high pressure will have modified and moved offshore, with southerly flow on its back side bringing in milder air. An Alberta clipper passing by to the north could bring light snow to the region by mid-week. There is the off chance that the clipper and its associated trough could pick up a system in the southern U.S. and cause it to rapidly intensify into a Nor’easter that would bring heavy snow to New England, but for now, this appears unlikely due to the progressive, fast-moving nature of the trough and the trough not digging far enough south to pick up a system in the southern U.S. With the southeast U.S. ridge likely making an appearance again afterwards and battling with arctic air to the north, storminess will likely return, but the chance of warm surges, ice, and rain will also return as well if the ridge becomes too strong.
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| Source: TropicalTidbits |
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| Source: TropicalTidbits |