What the polar vortex and a major winter storm in the U.S. means for Maritime weather

Kalin Mitchell shares the Maritime weather forecast for Jan. 22.

A deep dive southward of bitterly cold air created by a breakdown of the polar vortex will fuel a major winter storm in the United States stretching from Texas to New England. The Maritimes will also have frigid conditions this weekend as result of the arrival of that polar air. The storm moves out of New England Sunday becoming a Nor’easter that could impact the Maritimes with significant snowfall Monday.

The frigid weekend ahead

A cold and blustery day Friday, but temperatures take a real plunge Friday night as polar air arrives.

Low temperatures in New Brunswick will fall into a range of -18 to -24 with the wind chill making it feel into the -30s. Low temperatures for Prince Edward Island will range from -15 to -18, feeling into the -20s. For Nova Scotia, low temperatures will be between -12 and -17, with wind chills making it feel -18 to -24.

High temperatures on Saturday won’t be much better. Ranging -15 to -20 for New Brunswick, near -16 for Prince Edward Island, and -10 to -15 for Nova Scotia. The wind speed picks up for Saturday, sustained 20 to 30 km/h with gusts of 30 to 60 km/h. That will produce a wind chill making it feel well down into the minus-teens and minus-twenties through the day.

The frigid air blown over the Gulf of St. Lawrence and Bay of Fundy will produce flurries with a risk of snow squalls for eastern Prince Edward Island and most of Nova Scotia. The risk of snow squalls will be higher for a few areas of Nova Scotia including the southwest of the province, the Annapolis Valley, North Shore, and Cape Breton.

Storm watching

A low-pressure system moving out of Texas and across the southern U.S. has triggered winter storm watches and warnings stretching from that state to New England.

Parts of Texas, the Gulf States, the Midwest, Mid Atlantic, and New England are all expected to be impacted by either significant freezing rain, heavy snow, or a mix of both. This is about as good a setup you can have for a major winter storm for parts of the southern United States. A combination of polar air reaching much further south than normal and heavy moisture pulled off the Gulf of Mexico.

The winter storm then triggers the development of a Nor’easter that will move from the coastline of North Carolina, past Cape Cod, and then past the coastline of Nova Scotia. It is that part of the weather pattern that is most likely to impact the Maritimes on Monday.

The Nor’easter could get close enough to bring significant snow starting late Sunday night and continuing through Monday. As of Thursday afternoon, southern areas of New Brunswick, all of Nova Scotia, and eastern Prince Edward Island were looking most at risk of a heavy snow, defined as 15 or more centimetres.

This is still in the long-range forecast for this type of weather system. CTV meteorologist Kalin Mitchell expects to see variations in potential snowfall for the Maritimes over the next few days in available guidance. That guidance will improve on the weekend after the storm develops in the southern United States. There will be better and more information feeding into forecast models at that time.

Check frequently on the Sunday night and Monday forecast over the coming days. With the cold air in place and the expected strength of this storm if we catch it, it will be a disruptive snowfall.