Sunny and chilly today after snowstorm with very cold nights; turns milder this week but mostly dry except rain showers on Wednesday and a coastal storm possibly affecting eastern New England late week; generally chilly with snow still possible in early April

Plain-language summary:

 

After the snowstorm in central and northern New England yesterday, it is chilly and sunny today, with very cold temperatures last night and tonight where there is deep snow cover. It will turn substantially milder early next week, though moderated by deep snow cover, cold air damming, and lack of low-level southerly flow. It is mostly dry this upcoming week except some rain showers on Wednesday and a coastal storm that could affect eastern New England late next week. The weather pattern favors chilly weather with snow chances, especially in higher elevations, for early April.

Meteorological discussion:

The impressive spring snowstorm in central and northern New England is over. A cold high pressure over Quebec is now providing northerly flow with cold, dry air and sunshine dominating today. In northern New York, the fresh deep snow cover, clearing skies, and calming winds led to an exceptionally cold night for late March, with some places dropping to 0F (-18C). Farther east, clouds and wind prevented it from getting that cold. The fresh deep snow cover is reflecting much of the sun's warmth back into outer space, chilling the air, though the strong late March sun will still allow it to warm up to around or just above freezing in most lower elevation locations, and warmer in eastern Ontario which mostly missed the snowstorm. With high pressure providing clear skies and calm winds tonight, temperatures will plunge in areas with snow cover, down below 10F (-12C) in many locations.

 

Source: TropicalTidbits

Despite the cold high pressure in Quebec, upper-level ridging building along the U.S. East Coast will deflect the coldest air away from our region and back to the north over the next 2 days, allowing for a warming trend while remaining dry. At the same time, an upper-level trough and strong surface low pressure system will eject from the Rockies into the Plains and then the Upper Midwest U.S. before weakening as the storm heads way to our northwest over northern Ontario. By the time any remnant of the storm reaches our region by Wednesday, just some rain showers along a cold front are expected. The surface high pressure remaining to the northeast will provide northeasterly to easterly flow early next week, mostly blocking the pronounced warmup taking place farther west, especially in central and northern New England where cold air damming and deep snow cover will chill the air further.

 

Source: TropicalTidbits

By late next week, the cold front will have passed, and another storm will likely form off the East Coast. Early indications are that it will most likely be far enough east for its impacts to be limited to eastern New England, if even there, but it is too early to say for sure. That depends on how much it interacts with a northern trough that is expected to dive southeastward out of northern Ontario, a bit similar to yesterday's snowstorm. It will also turn cooler, but with no arctic air and most of the snow having melted by then, it won't be nearly as cold as this week. Long-range indications of some high-latitude blocking (-NAO) and western North American ridging (+PNA) favor chilly weather for early April, with perhaps more chances of spring snow, especially in higher elevations.

 

Source: TropicalTidbits

Source: TropicalTidbits

Source: Climate Prediction Center