Much of Canada can expect the coldest winter since 2013-14, says meteorologist
Author of the article:
Washington Post
Matthew Cappucci
Publishing date:Oct 15, 2021 •
Pedestrian walks down Brunswick Street in Halifax as major storm blasts the Maritimes on Feb. 2017. A La Nina pattern forming in the Pacific Ocean is expected to bring wet weather to Canada's western coast this winter, while a polar vortex could be pushed from the North Pole to the Prairies.
PHOTO BY ANDREW VAUGHAN/CANADIAN PRESS
After a months-long period of relative atmospheric balance between El Niño and La Niña, the National Oceanic and Atmospheric Administration announced Thursday that La Niña has returned. It’s expected to stick around in some capacity through the winter and relax toward spring.
Calgarians and southern Albertans should expect a colder than usual winter with lots of snowfall in the mountains, according a new AccuWeather report.
The report published Thursday says a La Niña weather pattern forming in the Pacific Ocean is expected to bring wet weather to Canada’s western coast this winter, while a polar vortex could be pushed from the North Pole to the Prairies.
“I believe we may see at least three extreme blasts of bitterly cold air dropping down into the southern Prairies this winter,” meteorologist Brett Anderson said in the online report. “This winter will likely end up colder than the winter of 2018-19 and the coldest winter since 2013-14 in the region.”
Anderson said temperatures could fall to as low as -30 C during those times. He is predicting a winter that is -2 C colder than average in the southern Prairies, with Alberta and Saskatchewan seeing the largest decreases in temperatures.
Accuweather predicts increased snow storms in the eastern provinces of Ontario and Quebec thanks to the polar jetstream. However, the reports says above-average temperatures are likely in store in Toronto, Ottawa and Montreal.
“While this winter does not look all that cold from Ontario to Quebec, it will be cold enough to support many opportunities for significant snowfall this winter,” said Anderson. “I expect a favourable winter with solid snow bases across much of ski country in eastern Canada and especially across Quebec.”
Judah Cohen, an atmospheric scientist and the director of Atmospheric and Environmental Research in Boston, says it’s just too early to know how other atmospheric players may influence the season, especially in the east coast.
“The most impressive atmospheric feature [lately] has been this ridge of high pressure over Eastern Canada,” he wrote in a Twitter direct message. “It has acted like an immovable boulder in the jet stream, and if that feature stayed park over Eastern Canada for much of the winter we would all be saying ‘what winter?'”
He does think that could change, but a transition like that is something that weather models struggle to anticipate.
“Where that block relocates will could be potentially critical to how the winter begins and may even set the tone for the winter,” he wrote.
“Abundant snowfall is expected throughout much of ski country from the Coastal Range of British Columbia through the Rockies of western Alberta,” said Anderson.
The Farmer’s Almanac is predicting “fair weather” throughout most of October and November, with colder temperatures rolling over the Rocky Mountains and stormy weather forming in the Prairies shortly before December.
The stormy weather is expected due to what is known as La Niña conditions. La Niñas occur every three to five years when jet streams are amplified, ushering in colder, stormy weather. Last year also saw La Niña conditions form in Canada.
The intensifying La Niña should peak in magnitude, or strength, by the end of 2021. In brief, here are some of the key impacts La Niña could have in the coming months:
• Extending favorable conditions for Atlantic hurricane activity this fall;
• Worsening drought conditions in the U.S. Southwest through the winter and potentially elevating the fire risk through the fall;
• Raising the odds of a cold, stormy winter across the northern tier of the U.S. and mild, dry winter across the South;
• Increasing tornado activity in the U.S. Plains and South during the spring.
During La Niña winters, high pressure near the Aleutian Chain shoves the polar jet stream north over Alaska, maintaining an active storm track there.
La Niña first arrived in fall 2020 before fading away in May 2021. Neutral conditions, bridging the divide between La Niña and El Niño, prevailed through the early fall before the NOAA’s declaration of La Niña’s return Thursday.
This season is running about 54% ahead of average in the Atlantic, but 28% behind typical norms in the Pacific. Usually if air is rising somewhere and enhancing storm prospects, sinking elsewhere has the opposite effect.
Abundant snowfall is expected throughout much of ski country
The polar vortex, the zone of frigid air surrounding the Arctic, has been showing signs of weakening or becoming more unstable as of late. A weak, unstable vortex is more prone to unleashing frigid air over compared to one that is strong and stable and that tends to lock up cold over the high latitudes.
“Once the polar vortex weakens, it could be predisposed to further weakening in the coming weeks or months and we have a more severe winter,” Cohen wrote.
But Cohen also said there are influences that could halt any vortex weakening. He mentioned a scenario in which “the polar vortex rapidly strengthens as we approach the beginning of winter and we have an extended mild period to begin winter and possibly persisting right through the end of winter.”
After a months-long period of relative atmospheric balance between El Niño and La Niña, the National Oceanic and Atmospheric Administration announced Thursday that La Niña has returned. It’s expected to stick around in some capacity through the winter and relax toward spring.
Calgarians and southern Albertans should expect a colder than usual winter with lots of snowfall in the mountains, according a new AccuWeather report.
The report published Thursday says a La Niña weather pattern forming in the Pacific Ocean is expected to bring wet weather to Canada’s western coast this winter, while a polar vortex could be pushed from the North Pole to the Prairies.
“I believe we may see at least three extreme blasts of bitterly cold air dropping down into the southern Prairies this winter,” meteorologist Brett Anderson said in the online report. “This winter will likely end up colder than the winter of 2018-19 and the coldest winter since 2013-14 in the region.”
Anderson said temperatures could fall to as low as -30 C during those times. He is predicting a winter that is -2 C colder than average in the southern Prairies, with Alberta and Saskatchewan seeing the largest decreases in temperatures.
Accuweather predicts increased snow storms in the eastern provinces of Ontario and Quebec thanks to the polar jetstream. However, the reports says above-average temperatures are likely in store in Toronto, Ottawa and Montreal.
“While this winter does not look all that cold from Ontario to Quebec, it will be cold enough to support many opportunities for significant snowfall this winter,” said Anderson. “I expect a favourable winter with solid snow bases across much of ski country in eastern Canada and especially across Quebec.”
Judah Cohen, an atmospheric scientist and the director of Atmospheric and Environmental Research in Boston, says it’s just too early to know how other atmospheric players may influence the season, especially in the east coast.
“The most impressive atmospheric feature [lately] has been this ridge of high pressure over Eastern Canada,” he wrote in a Twitter direct message. “It has acted like an immovable boulder in the jet stream, and if that feature stayed park over Eastern Canada for much of the winter we would all be saying ‘what winter?'”
He does think that could change, but a transition like that is something that weather models struggle to anticipate.
“Where that block relocates will could be potentially critical to how the winter begins and may even set the tone for the winter,” he wrote.
“Abundant snowfall is expected throughout much of ski country from the Coastal Range of British Columbia through the Rockies of western Alberta,” said Anderson.
The Farmer’s Almanac is predicting “fair weather” throughout most of October and November, with colder temperatures rolling over the Rocky Mountains and stormy weather forming in the Prairies shortly before December.
The stormy weather is expected due to what is known as La Niña conditions. La Niñas occur every three to five years when jet streams are amplified, ushering in colder, stormy weather. Last year also saw La Niña conditions form in Canada.
The intensifying La Niña should peak in magnitude, or strength, by the end of 2021. In brief, here are some of the key impacts La Niña could have in the coming months:
• Extending favorable conditions for Atlantic hurricane activity this fall;
• Worsening drought conditions in the U.S. Southwest through the winter and potentially elevating the fire risk through the fall;
• Raising the odds of a cold, stormy winter across the northern tier of the U.S. and mild, dry winter across the South;
• Increasing tornado activity in the U.S. Plains and South during the spring.
During La Niña winters, high pressure near the Aleutian Chain shoves the polar jet stream north over Alaska, maintaining an active storm track there.
La Niña first arrived in fall 2020 before fading away in May 2021. Neutral conditions, bridging the divide between La Niña and El Niño, prevailed through the early fall before the NOAA’s declaration of La Niña’s return Thursday.
This season is running about 54% ahead of average in the Atlantic, but 28% behind typical norms in the Pacific. Usually if air is rising somewhere and enhancing storm prospects, sinking elsewhere has the opposite effect.
Abundant snowfall is expected throughout much of ski country
The polar vortex, the zone of frigid air surrounding the Arctic, has been showing signs of weakening or becoming more unstable as of late. A weak, unstable vortex is more prone to unleashing frigid air over compared to one that is strong and stable and that tends to lock up cold over the high latitudes.
“Once the polar vortex weakens, it could be predisposed to further weakening in the coming weeks or months and we have a more severe winter,” Cohen wrote.
But Cohen also said there are influences that could halt any vortex weakening. He mentioned a scenario in which “the polar vortex rapidly strengthens as we approach the beginning of winter and we have an extended mild period to begin winter and possibly persisting right through the end of winter.”
Chris Fidler, left, of Halifax, and Ben Reigert, of Reading, walk out onto the ice at Sweet Arrow Lake, to fish on Saturday, Jan. 6, 2018, in Pine Grove, Pa. Freezing temperatures since December 26 have made for ideal ice fishing conditions.
PHOTO BY DAVID MCKEOWN /AP
If La Niña lingers into spring, it could enhance the upcoming severe weather season in Tornado Country across the Great Plains and Deep South. There is a demonstrable link between La Niña and a more active severe weather season.
NP, Calgary Herald and The Washington Post’s Jason Samenow contributed to this report.
If La Niña lingers into spring, it could enhance the upcoming severe weather season in Tornado Country across the Great Plains and Deep South. There is a demonstrable link between La Niña and a more active severe weather season.
NP, Calgary Herald and The Washington Post’s Jason Samenow contributed to this report.
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