Plain-language summary:
The active weather pattern continues, with first light to moderate snow tonight into Monday. A clipper brings a few snow showers Tuesday into Tuesday night followed briefly by a colder air mass. A bigger storm follows for Wednesday night into Thursday with mostly snow but a brief changeover to ice or rain is possible south of the U.S./Canada border. It turns colder afterward with a clipper likely producing some snow showers and squalls next weekend. It turns even colder afterward with more storminess likely through at least early February, likely eating away at the snow drought so far this winter south of the U.S./Canada border.
Meteorological discussion:
The active weather pattern continues. A northern disturbance will first bring light snow to eastern Ontario and southern Quebec this evening, mainly along and north of the St. Lawrence River. The slightly stronger southern disturbance with more moisture will follow right behind and spread snow to the rest of the area south of the U.S./Canada border. The southern disturbance will strengthen as it gives over the warm waters just off the East Coast, but too late for a major snowstorm for most. Still, as it is, it will consolidate its moisture closer to the low-pressure center and produce a band of moderate to heavy snow due to strengthening mid-level frontogenesis over southern Vermont to central Maine late tonight into tomorrow, leading to a jackpot of 8-12" (20-30 cm) there. With the strong lift roughly coinciding with the dendritic growth zone, it will be efficient at producing snowflakes, leading to a fluffy, high snow-to-liquid ratio and a possible overachievement in this area. This is especially true starting late tonight, whereas the snow in that area will be a little wetter before that but still rather dry and fluffy to the north. This evolution has been poorly modeled, with models showing a major storm moving northeastward a few days ago, then showed very little of a storm by a couple of days ago, and now show a last minute intensification just offshore but moving more east-northeastward. It is a rather dynamic situation and I expect that there will still be some surprises.
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| Source: TropicalTidbits |
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| Source: TropicalTidbits and PivotalWeather |
A clipper passing to the north will brings some snow showers Tuesday into Tuesday night, mainly just ahead of or along its cold front. It will only bring light snow accumulations of up to 2" (5 cm), with the highest amounts in eastern Ontario and on western or northwestern facing slopes of the Adirondacks and Green Mountains. Although it will not bring a lot of snow, it will provide a modified arctic air mass by late Tuesday night that will prove to be critical for the next storm immediately following behind it.
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| Source: TropicalTidbits |
The next storm will be stronger to start as it ejects from the southern Rockies into Texas. Given its strength and westward position, it will move northeastward into the Ohio Valley by Wednesday afternoon and then jump to southern New England by later Thursday due to coastal redevelopment. Although it is strong by itself, there is no additional disturbance to energize it further or make the trough negatively tilted and amplify more. So strengthening will be gradual and precipitation and snowfall amounts will not be epic for most. However, like most storms earlier in the winter, this storm will have more cold air to work due to the aforementioned modified arctic air mass and just being at the climatologically coldest time of the year. As such, precipitation looks to be mainly snow for most, although if the storm is stronger or tracks farther northwest, a changeover to freezing rain or even plain rain would occur, especially south of the U.S./Canada border. With the current expected storm track, the heaviest snow looks to occur in northwestern New York, eastern Ontario, southern Quebec, and northern Maine, but areas farther south in northern New England will still get a decent front end snow before getting dry slotted or changing to other precipitation types. The south or southeasterly low-level winds also look strong enough for terrain effects to occur, with precipitation shadowing in the Champlain and especially upper Connecticut River valleys, and enhanced precipitation in the eastern Adirondacks, southeastern slopes of the Green and White Mountains, and perhaps the Laurentians depending on how far north the storm tracks.
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| Source: TropicalTidbits |
Colder air follows behind this storm, with a clipper perhaps bringing snow showers and squalls next weekend, followed by even colder air. The arctic air is shifting from Asia into Canada and will become more readily available in our weather pattern to end January, likely ending the incredibly warm pattern so far this month. However, the southeast U.S. ridge will still fight back at times, limiting the intensity of the cold but also allowing for a battle zone for frequent storms to track on. If the southeast U.S ridge is not too strong, this could lead to a lot of snow, but if it is stronger, storms would cut into the Great Lakes, causing precipitation to change over to ice or even rain. There should be no lack of weather excitement through early February! This pattern will likely eat away at the snow drought so far this winter south of the U.S./Canada border.
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| Source: TropicalTidbits |
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