Genuine spring weather will be delayed for one part of the country, but other areas can expect an early taste of the season's warmth. AccuWeather meteorologists have all these details and more for the coming season.
The Montreal skyline as seen from Mount Royal on a sunny, late-spring day on June 7, 2021. (Maurizio Orlando / Hans Lucas via Reuters)
Spring is right around the corner, and for Canadians who have dealt with bitter blows from Mother Nature this winter, the flip of the calendar may not come soon enough. Residents eager for a spring preview have come to the right place as AccuWeather has released its annual Canada spring forecast this week.
The seasonal outlook, spearheaded by AccuWeather Senior Meteorologist Brett Anderson, who has decades of Canadian forecasting experience, offers expert insight on the main weather themes expected across the country.
In a similar fashion to the winter months, Anderson said, La Niña will carry over into the spring and play a key role in the overall weather pattern for the coming season. By studying past springs when this climatological phenomenon was present, forecasters can uncover clues on how the weather will unfold across the country this season.
Which areas will be the first to experience a spring thaw? And where could the transition to genuine spring weather be delayed? Read on for the complete breakdown of how the season is projected to play out across Canada as meteorological spring arrives on March 1 and the vernal equinox, the first official day of spring, comes on Sunday, March 20.
Spring weather to be delayed in western Canada
During a La Niña phase, when sea surface temperatures in the open waters of the equatorial Pacific Ocean dip to below-average levels, the atmospheric pattern favors a persistent southward dip in the jet stream across western Canada and into the northwestern United States. That jet stream setup has significant implications on the weather themes for the coming season.
Forecasters say that this type of jet stream orientation will open the door for waves of chilly air to linger across much of the western third of the continent, leading to a pronounced delay in springtime warmth.
On average, temperatures will be about 2-4 degrees Fahrenheit (1-2 degrees Celsius) below normal as a whole during the course of the season, according to Anderson.
During March, Vancouver, British Columbia, typically has high temperatures within a few degrees of 50 F (10 C), before eventually rising to around 60 F (15 C) by the middle of May. Farther to the north and east in Prince George, average temperatures steadily climb during March, from near 32 F (0 C) at the start of the month to 44 F (7 C) by the end. Toward the end of May, the city’s high temperature is usually in the upper 60s F (19-21 C).
Ocean water temperatures off the western coast of Canada are forecast to be slightly below normal through the spring, which will also contribute to the cool conditions, according to Anderson.
The lower-than-average temperatures will be accompanied by frequent bouts of precipitation, making it necessary for residents to keep not only extra layers but also rain gear close at hand.
“The close proximity of the jet stream, which is a pathway to storms, may lead to a stormier spring, especially across the southern half of British Columbia and up into the Rockies,” Anderson said.
This will result in a surplus of precipitation compared to normal for these areas, which could help to curb the abnormally dry to moderate drought conditions from expanding farther in central and eastern portions of British Columbia.
“The spring flood season may also be delayed due to this pattern," Anderson said. "However, significant snowpack deep into the late spring and early summer should keep area rivers and streams running at or above normal.”
Although the news of cool, stormy weather can be a disappointment to warm weather fans, winter sports fanatics will be thrilled that this setup could lead to an extension of the spring ski season for many resorts in the region.
Early warming predicted for the Prairies
As western areas wait on spring warmth, residents in central portions of Canada may be the first to experience a true taste of the season.
Anderson expects the eastern half of the Prairies, including a majority of Manitoba, will lie squarely within a zone where early-season warmups will produce above-average temperatures.
The spring thaw may initially prompt fears of flooding from rapid snowmelt, but, Anderson said, that risk is expected to be low due to a combination of factors.
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“With the expectation of below-normal precipitation from eastern Alberta to western Manitoba this spring, limited snowpack and less moisture frozen into the layer of earth just beneath the surface, the risk of major spring flooding appears to be slightly lower than normal this year,” Anderson said.
He added that during March and early April, a clearer picture would emerge on the exact threat level for significant spring flooding.
Even though the risk of flooding may be lower than in recent years, the combination of warmth and unusual dryness could lead to a completely opposite concern heading into the latter part of the season and into the summer months – wildfires.
The worst drought conditions across Canada can be seen across the southern tiers of Alberta, Saskatchewan and Manitoba during the latter part of the winter. (North American Drought Monitor)
Widespread severe to extreme drought is ongoing across the southern tiers of Alberta, Saskatchewan and Manitoba, and with the outlook of below-average precipitation across much of this region during spring, forecasters warn these conditions may expand and worsen.
To some extent, there is a concern for expanding drought, most likely late in spring, according to Anderson.
“There probably won’t be a widespread wildfire risk for most of the spring,” he added. “However, if dryness persists into June, then I would be concerned for a more widespread fire risk across the Prairies.”
Wet, mild pattern could raise flood concerns in Atlantic Canada
Farther east, another piece of the jet stream is expected to be directed toward southeastern and Atlantic Canada this spring, which will have significant implications on the temperature and precipitation outlook for this part of the country.
Cloudier and wetter conditions are forecast overall, especially from southern Ontario and into a large part of Atlantic Canada, which will contribute to above-average precipitation in the coming season, according to Anderson. To go along with that, Anderson added, "There will be opportunities for some significant coastal storms -- nor'easters -- in early spring for eastern Atlantic Canada."
Toronto has had a snowy winter so far. As of Feb. 23, the city has measured 50 inches (127 cm) of snow this season, which is already higher than the average seasonal snowfall, 48 inches (122 cm). Toronto has also already eclipsed last year's seasonal snowfall total of 49 inches (125 cm), and as Anderson pointed out, there is still the rest of February and March during which more snow could accumulate.
After that, precipitation in the form of rain will be a factor.
Toronto, Montreal, Ottawa and Quebec City all typically receive around 7-8 inches (180-200 mm) of precipitation, which includes rain and melted snow, during March, April and May. Residents in these cities and surrounding locales are likely to be reaching for umbrellas more often than they might during a typical spring as forecasters project the scales to be tipped to a precipitation surplus for these areas.
Saint John, New Brunswick, and Halifax, Nova Scotia, are two other larger areas that can be frequented by storms this spring. Both cities average around a foot (305 mm) of precipitation during the season.
In terms of the possibility of flooding due to frequent bouts of precipitation, AccuWeather experts say that the combination of a slow-thawing ground and heavy rainfall at times could spell trouble.
Spring flood concerns are expected to be elevated across the region, with rivers and streams in New Brunswick potentially most susceptible to spilling over their banks, Anderson warned.
River and stream flooding may not be the only concern as the season progresses, however. Residents around the Great Lakes will also need to be prepared for rising water levels.
“A stormier pattern means more wind storms, which, combined with the annual breaking up of the ice pack and above-normal water levels on lakes Erie and Huron, can be a recipe for a higher number of lakeshore flooding events this spring,” Anderson said.
Ice coverage on the Great Lakes as of Sunday, Feb. 20, 2022. (INOAA)
Ice coverage on the Great Lakes was close to 40% as of the last week of February, which was similar to the percentage at the same time last year.
Despite the unsettled weather pattern, temperatures across much of southeastern Canada are forecast to be around average levels, with above-normal warmth possible for parts of northeastern Nova Scotia and into Newfoundland.
The main storm track near or over Atlantic Canada will open the door for more southerly winds to flow in from off the Atlantic Ocean, according to Anderson.
Above-normal water temperatures in the northwest Atlantic will also play a role in the mild pattern for this part of the country.
“The nearby ocean water may be as much as 2-5 F (1-3 C) above normal during the spring,” Anderson said.
This will help to keep air temperatures in populated areas along the coast above normal, especially during the overnight hours.
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