Environment Canada is forecasting "significant winter weather" to arrive in Windsor-Essex on Thursday evening or Friday morning.
It is "likely that holiday travel will be significantly impacted," the agency warns.
Environment Canada says there is potential for an ice storm for some areas Saturday night into Sunday.
Meanwhile, meteorologists at CBC's Weather Centre are advising against travel on Friday and over the weekend.
"Considerable uncertainty exists regarding which locations will be most severely impacted, but it appears that areas along the Highway 401 corridor have the greatest likelihood for significant freezing rain amounts," Environment Canada warns.
Pelee Island on Thursday warned that winter air service from Windsor to the island could be disrupted by freezing rain Friday through Sunday.
According to a weather statement issued by Environment Canada, several disturbances originating in Texas are expected to move towards the Lower Great Lakes.
The agency says precipitation is expected to spread into southwestern Ontario on Thursday evening and through the remainder of southern Ontario by Friday morning.
The exact location of this storm track will determine whether the precipitation falls as rain, freezing rain, ice pellets, or snow.
Environment Canada's most recent assessment suggests that precipitation could fall as snow, ice pellets, freezing rain or periods of rain in Windsor-Essex.
Areas north of a line from Kincardine to Barrie to Ottawa are likely to see mainly snowfall totaling nearly 10 cm possible, the statement says.