Environment Canada has issued a snow squall watch for Waterloo Region and northern parts of Wellington County.
The agency said it is expecting lake effect snow beginning on Tuesday morning and continuing into early Wednesday morning.
Poor visibility, possible whiteout conditions, and 10 to 20 centimetres of snow are expected in some areas.
The worst snow squall conditions are expected on Tuesday afternoon, Environment Canada said and drivers should be prepared for “hazardous winter driving” conditions.
“Snow squalls cause weather conditions to vary considerably,” Environment Canada said. “Changes from clear skies to heavy snow within just a few kilometres are common.”
The weather office added that residents should consider postponing non-essential travel until conditions improve.