Lake effect snow moved across southern Ontario on Thursday, just in time for the evening commute.
"This phenomenon occurs when cold air moves over warm water," explains Brian Dillon, a meteorologist at The Weather Network.
In some places, traffic slowed to a crawl as large snowflakes blanketed roadways, causing slippery conditions and reduced visibility.
"I think the sudden blast of snow was enough to catch some drivers off guard," says Dillon.
Especially since the last time the region saw a significant snowfall was back on Boxing Day when around 10 cm piled up.
Drivers should be prepared for another light dusting Friday, before the precipitation changes over to rain on Saturday.
"The Greater Toronto Area could see some light snow showers Friday afternoon, with less than 5 cm expected to fall," says Dillon. "From Barrie to Oshawa and east into Brockville up to 10 cm is forecast through Saturday."
In parts of northwestern Ontario, snow squalls will continue to produce local heavy and blowing snow Friday morning.
Motorists are urged to adjust their driving habits accordingly and slow down as conditions and visibility deteriorates.
In addition to the snow, cold temperatures will leave residents dressing in layers.
A frostbite warning was issued in Ottawa Friday, as the windchill will make things feel closer to -20 through the day.
Ottawa Public Health is reminding residents to keep an eye out for those most susceptible to the cold including the elder, children and the homeless.
It doesn't take long for frostbite or hypothermia to set in, so it's important to keep warm as the temperature drops.
"A warm front pushing in on Saturday however, will help temperatures to rise once again," adds Dillon. "Many places will see above seasonal conditions before another sharp drop in temperatures Sunday."
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