Showers today and Monday, then drier Tuesday and Wednesday, then unsettled late week, then turning colder and perhaps drier next weekend into early the following week

Plain-language summary:

 

After the unsettled weather pattern over the past several days, and having a brief break last night into this morning, showers will enter our region again this afternoon, though only light rain is expected. Afternoon scattered showers are expected tomorrow before it truly dries out on Tuesday and Wednesday with seasonably mild temperatures. A weakening storm will bring showers later in the week, before it turns cooler and perhaps drier next weekend, though there is the possibility of mostly higher elevation snow as the cold air comes in. The cool pattern could last several days or longer, though how long it lasts is unclear.

 

Meteorological discussion:

 

After the showers over the past several days, there was a brief period of drying and clearing late last night into this morning. However, another weak disturbance is already moving into the region. With the weak low pressure system passing just to the south, we will be on the cooler, more stable side of the system, with just light rain (no convective or heavy rainfall) expected for our region.

 

Source: TropicalTidbits

 

That weak system will quickly move out to sea by later tonight, but a deepening upper-level trough and associated cold air aloft on Monday will lead to instability in the afternoon due to the strong April sun heating the boundary layer. Scattered showers, possibly mixed with graupel or small hail, are expected throughout the region. A cool (but still seasonably mild) high pressure will dry it out on Tuesday and Wednesday before the next storm approaches from the central Plains. The storm will be weakening, but warm air colliding with the prior cool air mass and maritime-cooled air mass by the still cool western Atlantic waters will lead to showers on Thursday and Friday, especially from Vermont on westward. Maine could escape the rain almost entirely as the storm just fizzles out as it moves eastward.

Source: TropicalTidbits

 

Source: TropicalTidbits

 

Afterward, a trough will dominate over eastern North America, providing a widespread dose of cold air from central Canada, which has been rather uncommon for the past few months. Widespread nighttime freezes will occur, even in the broader, warmer valleys. If a cold air comes in with a broad surface high pressure, it will just be cool and dry with mostly sunny skies for several days. This appears to be the most likely scenario, but there is also a lesser possibility of a storm coming up the Northeast U.S. coast into the cold air mass at some point, which would lead to late-season snow in some areas, especially in higher elevations. It is not clear how long the cooler pattern will last, but a slightly negative NAO and AO could favor it lasting a bit longer than most recent cold spells, although the near neutral PNA is not the most favorable for persistent cold in our region, and it will most likely have warmed back up by the end of April.

 

 

Source: TropicalTidbits

 

 

Source: Climate Prediction Center