Frigid air spilling into Ontario with dangerous wind chills
Bitterly cold temperatures are settling into Ontario for the opening days of March
We’ve just entered the beginning of meteorological spring, yet it’ll feel like the heart of winter out there over the next few days as a bitterly cold air mass settles across southern Ontario.
Temperatures that began falling early Saturday will bottom-out by the end of the weekend. Overnight wind chill values will approach -30 for parts of the Greater Toronto Area (GTA), with even colder wind chills expected farther north.
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With the thaw earlier this week and the colder temperatures here again, there is the risk of more potholes forming on some of the streets. Motorists will need to be mindful when on the roads this weekend.
This weekend: Significant temperature nosedive to begin March
Frigid temperatures spilled across Ontario through the day Saturday. Expect bitterly cold mornings both Sunday and Monday. Temperatures will come in as much as 15 degrees below seasonal over the next few days.
Wind chills will dive close to -30 Saturday overnight, even for areas near and in the GTA, including Orangeville, Markham and Whitby. Elsewhere, it gets even colder in eastern and northeastern sections, with feels-like values closer to -35 in Ottawa, Timmins and Sudbury.
It’s possible that this brief spell of cold weather will feature the coldest temperatures of the season for some communities across southern Ontario.
The coldest we’ve been in Toronto this season was -18.5°C back on Jan. 22. Ottawa’s coldest temperature of the season was a -23.8°C reading on Feb. 2.
This Arctic chill isn’t going to stick around very long, though. While Monday morning will feature bitterly cold temperatures, Tuesday morning will see readings rise 5 degrees above seasonal as our high-pressure system shifts east and allows southerly winds to blow across the border.
Beware health hazards, infrastructure strain
Temperatures this cold will pose a threat to life and property.
Frostbite can develop in as little as 10 minutes when wind chill values are in the -30s. Fingers, toes, and ears have the highest risk of developing frostbite. Extreme cold can irritate the lungs, particularly for those who live with asthma and other respiratory conditions.
Outdoor workers and folks who are homeless are at the highest risk of dangerous exposure to the cold air.
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There’s also an increased risk for carbon monoxide poisoning as residents try to stay warm through these frigid nights.
The cold weather could also lead to some impacts on infrastructure throughout the region. Extreme freeze-thaw cycles can lead to potholes in roads and bridges, as well as burst pipes. Water mains can crack and lead to significant flooding and water outages.
Public transit may experience delays as the extreme cold freezes switches and hydraulic systems slow down. Fluctuating temperatures can also create thin and uneven ice surfaces, leading to dangerous ice conditions throughout the region.
Lake-effect snow should soon stop for now
The good news, however, is that the lake-effect snow that whipped across parts of southern Ontario should finally draw to a close by Sunday afternoon as a wind shift disrupts the process across Lake Huron.
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Thursday’s snowfall helped push Toronto to record its snowiest February on record. We picked up 78 cm of snow through Feb. 27, just beating Feb. 2008 for the title of snowiest second month of the year. Over in Ottawa, this is the capital city’s snowiest February in 53 years.
The snowy trend won't be ending with the month. More snow is on tap to kick off March as we begin to see a roller-coaster shift into spring.
Stay with The Weather Network for all the latest on conditions across Ontario.