By CBC News

Police in southwestern Ontario are working with emergency crews near Sarnia to try to rescue motorists left stranded on a highway in extreme winter weather.

Ontario Provincial Police Sgt. David Rektor told CBC News Tuesday that police believe nearly 300 people are still stuck on Highway 402.

Military aircraft are also in the area to help with the search and rescue effort, said Canadian Forces Capt. Jennifer Jones. She told CBC News that a Hercules aircraft was airborne doing a weather check.

Emergency Management Ontario issued what it called a "red alert" for the area between Sarnia and London because heavy snowfall was causing zero visibility, while police recommended against any unnecessary travel between the two cities.

Over the weekend, drivers across Ontario and Quebec were involved in hundreds of accidents as dropping temperatures and wet weather made roads slick and dangerous.

Most of the accidents were minor, with many cars sliding into ditches. Police in both provinces are advising drivers to avoid following cars too closely and allow plenty of time to stop.

Read more.

During the winter months, safety experts advise drivers to have an emergency kit in the vehicle, with items like flashlights and jumper cables. Are you prepared for winter driving emergencies? Do you know how to handle treacherous road conditions like driving on black ice or getting your car out of a snowbank? Let us know in the comments below if you have questions about winter driving safety. You can also email us at yournews@cbc.ca. We'll forward some of your questions to a driving expert who can tell you the best courses of action.