Weather alerts issued in the northeast for expected first accumulating snowfall, heavy rain and severe thunderstorm

Environment Canada issued weather alerts Wednesday in anticipation of severe thunderstorms, heavy rain the first accumulating snowfall of the season in the northeast with up to 10 cm expected.

Environment Canada weather alert map for northern Ontario. Oct. 30, 2024. (Red - Severe thunderstorm warning or rainfall warning, Grey - special weather statement)

The above-seasonal temperatures in the region Wednesday are not expected to last as rain turns to snow Thursday with a steep drop in temperature from a high of 18 C to a low of -4 C forecasted in Timmins.

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Snow up to 10 cm

The northern portions of the northeast, particularly Wawa to Timmins, will be affected most by the messy weather.

"Snow may be mixed with ice pellets or freezing rain at times Thursday afternoon and evening," Environment Canada said Wednesday morning in a special weather statement.

"Snow is expected to taper to flurries Friday morning. Total snowfall amounts are fairly uncertain, however, snowfall amounts near 10 cm are possible."

Travellers should prepare for quickly changing and deteriorating road conditions.

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Communities along Highway 11 included in the weather alert are Matheson to almost Longlac.

Severe thunderstorm warning

Also in the Wawa area, Environment Canada issued a severe thunderstorm warning Wednesday morning.

"At 9:44 a.m. EDT, Environment Canada meteorologists are tracking a severe thunderstorm capable of producing strong wind gusts and up to toonie size hail," the weather warning said.

"This severe thunderstorm is located near Pukaskwa National Park, moving east at 95 km/h."

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As of 10:19 a.m., the severe thunderstorm warning ended for Wawa, Geoff Coulson, a warning preparedness meteorologist told CTVNewsNorthernOntario.ca in an email.

"(The warning) will likely end shortly for the White River area as the storm cells are moving fairly quickly," Coulson said.

"However, it may be expanded northeastward as the cells involved continue tracking in that direction."

When threatening weather approaches, Emergency Management Ontario said to take cover immediately.

"Lightning kills and injures Canadians every year," the weather alert said.

"Remember, when thunder roars, go indoors!"

In addition to causing injury, large hail can damage property.

"Strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles," Environment Canada said.

Rainfall warning

A rainfall warning has been issued for the Sault Ste. Marie area that stretches to Massey.

Nearly 60 mm of rain is expected by Friday morning, with slightly higher amounts possible in embedded thunderstorms.

"Rain will begin this afternoon and continue through Friday morning as a low-pressure system begins to affect the region," the weather alert said Wednesday morning.

"Total rainfall amounts near 60 mm are expected … Rain will taper and transition to scattered showers or flurries Thursday night into Friday morning."

Flash floods and water pooling on roads can be caused by heavy downpours.

"If visibility is reduced while driving, turn on your lights and maintain a safe following distance," Environment Canada said.