Environment Canada issued a snow squall watch for Sarnia-Lambton on Thursday afternoon.
The national weather agency is forecasting locally heavy snowfall with accumulations of 20 cm to 30 cm, along with near zero visibility at times in heavy and blowing snow.
Lake effect snow squalls off Lake Huron are expected to develop late Friday evening. They'll likely continue through Saturday morning before tapering off to light flurries Saturday afternoon.
Environment Canada said snow squalls can cause weather conditions to vary considerably; changes from clear skies to heavy snow within just a few kilometres are common.
Travel may be hazardous due to sudden changes in the weather, and road closures are possible.
Residents are being asked to consider postponing non-essential travel until conditions improve.
If you must travel, keep others informed of your schedule and destination and carry an emergency kit and mobile phone.
For information on emergency plans and kits go to www.getprepared.gc.ca.
