Plain-language summary:
After a cold night last night, it is turning somewhat milder today while staying mostly sunny, but a storm will bring a period of light rain tonight, then a warmup with breezy conditions, and then showers tomorrow evening and much cooler air behind it, with more breezy conditions. The weather pattern will then slow down, with it staying dry and slightly cool for several days, before a storm could bring a soaking rain to our region after next weekend depending on the storm's exact track and timing. It looks to turn colder for a while afterward, with the first widespread snow possibly occurring then.
Meteorological discussion:
After a brief cold snap yesterday into last night, surface high pressure moving offshore the U.S. East Coast is already bringing in somewhat milder air from the southwest today, with mostly sunny skies, though mid and upper-level clouds are increasing from west to east ahead of two separate and fast-moving low-pressure systems that will interact with each other on Monday and sort of phase on Monday night. Like with many low-pressure systems this fall, the moisture return isn't that impressive, and the strongest dynamics will go north of the U.S./Canada border, where the low-pressure systems will track. However, a period of light rain is likely for almost everyone with the warm advection tonight, though the southwesterly wind downsloping off the Adirondacks could mean very little rain falls in the Champlain Valley. As the low-pressure systems pass to our north on Monday, our region will enter the warm sector with breezy southerly and southwesterly winds, especially in the Champlain and St. Lawrence Valleys where wind channeling will enhance the wind. There will be some sunshine to promote daytime heating, making for a rather warm day for November. However, the second system passing to the north Monday night will drag a strong cold front through Monday night with showers and gusty winds.
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| Source: TropicalTidbits |
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| Source: PivotalWeather |
Tuesday will be quite breezy with a strong pressure gradient between a relatively cold (though not arctic) surface high pressure over the Great Lakes and a moderately strong low-pressure system in New Brunswick leading to strong, cold northwesterly winds. As the surface high pressure approaches Tuesday night, winds will turn nearly calm except over Maine, leading to good radiational cooling and a hard freeze for almost everyone except southern Maine. Even Maine will see a freeze Wednesday night as the surface high continues to move east.
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| Source: TropicalTidbits |
Starting the middle of next week, the weather pattern slows down as a blocking ridge begins to build near Greenland and slowly retrogrades westward (-NAO). This will lead to a slow-moving closed off upper-level low over Atlantic Canada promoting persistent northerly flow of dry, continental air in our region, preventing any precipitation (possibly except Maine and eastern Quebec which might be far enough east to be affected by the upper-level low) or real warm up. It will also push a weakening storm over the Great Lakes to our south on Friday. There isn't much cold air either though, so temperatures will be just near or slightly below average. The -PNA promoting continued troughs and storms in the western U.S. will promote a ridge over the central and eastern U.S., though the Greenland blocking will likely prevent most of the warmth from reaching our region. Still, the storm coming out of the Rockies next weekend could reach our region next weekend and bring a widespread soaking rain early the following week if it doesn't get squashed to the south by the blocking pattern, a rarity this fall. The timing is also uncertain given the slowly-moving weather pattern and the potential for any storm to cut off from the main jet stream and then take many days to move eastward. There will likely not be enough cold air for any widespread snow. Beyond that, an upper-level ridge will likely build over the western U.S. (neutral or slightly positive PNA), and combined with the high-latitude blocking, should finally bring in a notably cold air mass across eastern North America in about 10 days. This will likely also push the storm track southward, and it is possible or likely that we see the first widespread snow at some point around this time; we just need a storm to track just to our south and meet with the cold air that will be in place.
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| Source: TropicalTidbits |
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| Source: TropicalTidbits |
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| Source: Climate Prediction Center |
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