A big blast of winter hit southwestern Ontario Thursday afternoon and it caused some chaos on the roads.

Police responded to dozens of crashes as the snow started piling up.

In Courtland, two men were taken to hospital after a car and pickup truck collided on Highway 59.

Environment Canada says Waterloo, Kitchener, Cambridge, Guelph, Brantford, Woodstock and surrounding areas could get between 5 and 10 centimetres of snow starting Thursday afternoon.

The agency issued a winter weather advisory saying slippery roads could cause problems for drivers Thursday and possibly into Friday morning.

Waterloo, Kitchener and Cambridge have all declared snow events. Residents are asked to remove any vehicles parked on city streets by 11:59 p.m. Thursday. The parking ban will remain in place for 24 hours.

The snow is expected to taper off by Friday.