Plain-language summary:
The very dry and increasingly warm weather
across the region will gradually turn colder starting today and continuing
through Wednesday, though it will not be particularly cold for February. A snowstorm
will affect the southern Adirondacks to southern Maine on Tuesday, with it
being mostly dry to the northwest. A clipper will likely bring light snow to at
least southwestern parts of the region late Thursday into early Friday before it turns even colder
for next weekend. Storminess will likely return for the following week and
possibly last for several weeks, with it being potentially the snowiest and
most wintry part of the otherwise lackluster winter so far.
Meteorological discussion:
After an incredibly dry and
increasingly warm stretch over the past week, colder air will gradually move in
starting today and continuing through Wednesday. However, in the process, a
storm currently in Texas will move east-northeastward and strengthen. Its
northward movement will be limited by upper-level troughing and confluence to
the north and northeast, and the lack of a strong northern trough just to the
west to pick up and sling the storm northeastward. However, these storms laden
with Gulf of Mexico and western Atlantic moisture produce a lot of latent heat
from condensation and convection, which can be difficult for models to resolve,
and they often move farther north than models show just a few days in advance.
Indeed, models have trended northward for the past couple of days, though not by much, and this
still limits the heavy snow to the southern Adirondacks to southern Maine on
south, with light snow just to the north, and nothing from the Champlain Valley on northwest. Such intensifying storms produce a frontogenetic band of
very heavy precipitation on the northwestern side, typically farther northwest than
models show, and it will be cold enough for any precipitation to fall as snow. A
narrow area of 10"+ (25 cm) is likely in this area, but the fast movement of the storm will prevent truly epic snowfall amounts despite isolated snowfall rates of 2-3"/hr (5-8 cm/hr).
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| Source: Myself |
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| Source: TropicalTidbits |
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| Source: TropicalTidbits |
After the storm moves offshore Tuesday night, cold but not really arctic air moves in directly from the north-northwest without modification over the Great Lakes, with dry conditions dominating for Wednesday and early Thursday except perhaps some lake-effect snow showers downwind (south-southeast) of the unusually ice-free Lake Champlain. A clipper will dive southeastward from northern Ontario and will potentially be aided by some energy coming from the Midwest U.S. later Thursday into early Friday, which likely will bring light snow to areas from a line from western Quebec to southern Maine on southwestward. Accumulations will be limited by the moisture-starved nature of the clipper, as with any system coming from the northwest, though cold temperatures mean that any precipitation that does fall will be efficient in producing snow accumulation. There is some chance that the system strengthens enough due to the boost provided by the Midwest U.S. energy to provide enhanced snow, more than is typical of a clipper, perhaps up to 4-6" (10-15 cm) in some areas, especially in southern and eastern Ontario, where the clipper is likely to reach peak intensity before weakening as it moves southeastward into eastern New England and then offshore on Friday.
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