Environment Canada has issued a winter storm watch for Sarnia-Lambton.
The notice is in effect for Wednesday through Friday.
The national weather agency said rain showers on Tuesday night will transition to snow by early Wednesday morning.
Between 20 and 30 centimetres of snow is expected before tapering off by Friday morning.
Wind gusts of up to 70 kilometres per hour are expected, with reduced visibilities in heavy and local blowing snow.
We're being urged to take our time and be careful on area roadways.