A snow squall warning is in effect for the Barrie, Collingwood and Hillsdale areas.
The snow squall watch issued by Environment Canada on Thursday morning has now been upgraded to a warning.
Officials say a snow squall is expected to pass through the region late this afternoon along a cold front. Northwesterly winds behind the cold front will develop snow squalls this evening.
The weather agency says heavy, blowing snow will cause visibility to be significantly reduced, and the snow will accumulate quickly.
Environment Canada says some areas could see more than 15 centimetres of snow accumulation by Friday.
The agency is warning drivers that sudden changes in the weather could make travel hazardous.
“If visibility is reduced while driving, slow down, watch for tail lights ahead and be prepared to stop,” the statement reads.
Officials say the snow squalls will persist into Friday.
© 2018 Global News, a division of Corus Entertainment Inc.