Light snow and near-freezing temperatures could make for a tricky drive during the Friday morning rush.
Environment Canada has issued special weather statements covering southern, central, eastern and northeastern Ontario.
In Toronto, there's a chance of freezing drizzle and fog patches before noon, then again Friday evening before changing over to rainfall.
General amounts of 10 to 25 millimetres of rain are expected and for most areas the rain will end Saturday afternoon.
Across eastern Ontario, freezing rain is likely overnight and during the early morning hours Saturday. The freezing rain is most likely east of a line from Burk's Falls to Brockville and warnings may be issued.
The freezing rain will change to rain across eastern Ontario Saturday morning and the rain may persist until Saturday evening.