If you were hoping for a white Christmas, Environment Canada says it's a step closer to reality.
The weather agency has upgraded its winter storm watch to a winter storm warning for most of southern Ontario early Thursday morning as a significant winter storm moves across North America and bears down on the region.
Most of Thursday will be relatively quiet, but the changes in the weather will begin to happen Thursday evening and early Friday morning.
"Precipitation is expected to begin as rain or snow late Thursday afternoon or early Thursday evening before transitioning to rain for many areas Thursday night," read the warning from Environment Canada. "Temperatures are expected to plummet on Friday morning, leading to a potential flash freeze. Rapidly falling temperatures will be accompanied by damaging winds along with snow heavy at times. Extensive blowing snow will develop Friday morning. Very cold wind chills are expected to develop on Friday and persist into the weekend."
Any flash freeze may result in wet surfaces becoming slippery almost right away, creating hazards on roads.
Wind gusts may reach 100 kilometres per hour in some areas, with snowfall ranging from five to 15 centimetres by Friday night, Christmas Eve.
Environment Canada discourages travel under these conditions. If you must travel, give yourself extra time to reach your destination and plenty of stopping distance.
"Public Safety Canada encourages everyone to make an emergency plan and get an emergency kit with drinking water, food, medicine, a first-aid kit, and a flashlight," read the warning.