Another cloudy, unsettled period before another cold shot moves in; more sun later in the week with nighttime frost/freeze potential with possible influence from Ian next weekend

Plain-language summary:

It will be cloudy and unsettled with rounds of showers from today through Tuesday. However, total rainfall will be much less than earlier this past week. Some of the showers could be strong Monday afternoon, especially west of Maine. A cold shot will follow on Wednesday with more sunshine Thursday and Friday with nighttime frost and freezes away from the broader valleys and coastal areas. Temperatures will then warm up modestly, with Ian possibly influencing the weather next weekend but could also miss to the south.

Meteorological discussion:

Today marks the beginning of another unsettled period in the region. However, with tropical moisture not infused into the weather pattern, total rainfall will be far less than earlier this past week. It has been pretty cloudy west of the Vermont/New Hampshire border while decent sunshine continues east of there. Light stratiform-type showers are moving from southwest to northeast, reaching eastern Ontario and northwestern New York first early this afternoon and then reaching Maine by early tonight. There will be a break tonight though it will still be fairly cloudy. 

Source: PivotalWeather

However, showers will re-form and become more widespread again on Monday, especially in the afternoon, as a broad upper-level low approaches and induces some modest instability via cold air aloft. A few breaks of sun will help warm surface temperatures slightly and steepen lapse rates, especially south of the U.S./Canada border, causing some of the showers to be strong, producing thunder, small hail, and gusty winds. As is almost always the case this late in the year though, there will not be enough instability for truly severe thunderstorms. Maine might avoid the showers during the day as the upper-level low might be too far to the west. 

Source: PivotalWeather

A cold front will bring more showers Tuesday afternoon and evening and another chilly air mass for Wednesday with breezy northwesterly winds. There will still have abundant cloudiness and some showers on Wednesday due to the weakening upper-level trough centered over our region, especially along and northwest of the Appalachians. As is typical in the post-frontal northwesterly wind regime, it will be sunnier and drier to the southeast of the Appalachians. 

As the upper-level trough moves out and a broad surface high pressure moves in for Thursday and Friday, sunshine will become more abundant and winds will weaken. With the cool air mass still in place, frost and freezes are likely away from the St. Lawrence and Champlain Valleys as well as areas close to the Atlantic coast. As the broad high pressure slowly moves east, the cool air mass will moderate and there will likely be a least two or three mostly sunny days over the region, a rarity recently. 

The broad high pressure in the eastern U.S. will also cause then Hurricane Ian's movement to slow down over the eastern Gulf of Mexico. Ian will slowly move northward into the southeastern U.S. and weaken, eventually transitioning into an extratropical system as it encounters the mid-latitude temperature gradient. However, there will not be a favorable jet or trough interaction like with Fiona a couple of days ago, so Ian will weaken and be mostly a rain-maker for the mid-Atlantic U.S. A cold front might shove Ian offshore before it reaches our region, but that is not guaranteed yet. If it has any effect on our region, it would likely be nothing more than some moderate rains and some gusty winds. There is a possibility of a warmup afterwards, but that is rather uncertain especially given how recent modeled warmups have busted.

Source: TropicalTidbits