Weather statement issued ahead of stormy Friday for the Maritimes

How a major winter storm crossing the county evolves into rainy and windy weather for the Maritimes for the end of this week.

A major winter storm will bring severe weather conditions from Alberta to Quebec over the next two days. On Friday the Maritimes will be impacted by the powerful weather system, but unlike the Prairies, it is expected to rain instead of snow here.

The strengthening Alberta Clipper will run along southern areas of Alberta, Saskatchewan and Manitoba Wednesday through Thursday.

That path will swipe a band of heavy snow and high winds from southeastern Alberta across southern Saskatchewan and Manitoba. A Yellow Warning – Winter Storm in Alberta becomes an Orange Warning – Blizzard through Saskatchewan and Manitoba. Snow totals for the areas under the winter storm and blizzard warnings could reach 10-to-25 cm.

Peak gusts of 60-to-90 km/h will combine with the snow to create extensive areas of very poor visibility. The criteria for a blizzard warning are at least four hours or more of 40 km/h winds or higher, reducing visibility to 400 metres or less in blowing snow.

Weather conditions are forecast to impact Wednesday night in Saskatchewan. Conditions are forecast to improve through Thursday in Manitoba.

Ontario and Quebec snowstorm

The storm then goes on to impact areas of Northern Ontario and Northern Quebec with heavy snow Thursday into Friday. A series of winter storm watches and winter storm warnings have been issued for areas expected to be impacted.

One of the snowiest areas is expected to be from the Lake Nipigon area in Ontario to southern coastline of James Bay including the Moosonee area. For that area, a widespread snowfall of between 30-and-60 cm (one-to-two feet) looks likely Thursday through Friday evening.

Southern Ontario is expected to be swept by rain and high winds Thursday night into early Friday morning. Similar conditions are expected for the Maritime provinces Friday afternoon into Friday night.

Rain, wind for the Maritimes

At 4 p.m. Wednesday, Environment Canada issued Special Weather Statements covering southern New Brunswick, Prince Edward Island, and Nova Scotia. The statements are valid from Friday afternoon through Saturday afternoon. They call for potential wind gusts of 80 to 100 km/h and rain that could exceed 25 mm. The weather agency warns there could be travel service disruptions and possible power outages due to the strong winds.

With the centre of the storm forecast to move up the St. Lawrence River Valley, the Maritimes will end up on the milder and rainy side.

The pressure gradient between the storm to the west and high pressure to the east drives a strong southerly wind. The southerly wind will bring milder air up the eastern seaboard into the Maritimes bringing temperatures that could reach 10-to-14 degrees as the rain and wind moves in.

Rain will reach western New Brunswick and southwestern Nova Scotia Friday afternoon. The rain will develop across the Maritimes Friday evening and night. The rain will then clear the Maritimes, west-to-east, overnight through early Saturday morning.

A general 15-to-40 mm rainfall can be expected for the region. Keep in mind there will be snow and ice melt that adds to the runoff.

The ground is also frozen, which can contribute to more water runoff compared to similar rainfall in the warmer months. If you can clear property drainage of any snow or ice, that will help handle the rain.

As the rain moves in Friday, the wind becomes stronger. A southerly wind with widespread gusts of 50-to-80 km/h is expected to develop Friday afternoon and evening. Peak wind gusts could approach 90 km/h on exposed areas of the coast and at higher terrain.

Stronger gusts in excess of 120 km/h are very likely for the area of Inverness County – Cape Breton from Margaree Harbour to Cape North because of the topography of the Cape Breton Highlands. Those very strong winds are likely Friday evening through early Saturday morning.

The high wind is also likely to disrupt ferry travel services. You should check service provider websites for any delays and cancellations. You may also wish to secure any holiday decorations that could be damaged by the wind. No need for Rudolph to go on a pre-Christmas flight.