Residents in the Barrie, Collingwood and Orillia areas could see the first snowfall of the year on Wednesday.
According to a special weather statement issued by Environment Canada, snow is expected to hit the region Wednesday evening.
The weather agency says the snow is due to lake effect.
Officials say a cold front will pass through southern Ontario Wednesday afternoon, and will bring with it a strong northwesterly flow over warm lakes. This will produce large lake effect flurries off Lake Huron and Georgian Bay.
Environment Canada is warning residents that flurries can cause sudden reduced visibility and are reminding drivers to take extra precautions in poor conditions.
While Environment Canada says the accumulation is not expected to be significant, some areas, especially over higher terrain can expect a few centimetres of snow.
The snow is expected to last until Thursday morning.