A special weather statement has been issued by Environment Canada.
Meteorologist Geoff Coulson explains it's the result of a Colorado Low which will hit northwestern Ontario over the next 24 hours.
He indicates Thunder Bay will see mostly rain from the system until the overnight hours when the city is expected to start seeing about 4 to 8 cm of snow before it tapers off tomorrow.
Coulson tells us winter storm warnings are out for areas west of us including Dryden, Fort Frances and Lake of the Woods saying those communities, along with Ignace, Atikokan and Kakabeka Falls, could see 10 to 20 cm of snowfall.
Coulsen predicts colder temperatures tomorrow.