Environment Canada has issued a special weather statement for Hamilton that includes warnings of freezing rain, snow and much colder temperatures over the next 48 hours.
The weather agency warns that "mild and rainy conditions are expected over much of southern Ontario today, tonight and into Friday."
Environment Canada says that rain is expected to become more widespread tonight and into Friday.
"A general rainfall of 10 to 20 mm appears likely, although some areas may see higher amounts," Environment Canada said. "This rainfall in combination with the melting snowpack may result in pooling of water on roads and low-lying areas."
The agency says a "very strong cold front will cross the region from northwest to southeast on Friday bringing an abrupt end to the mild spell."
After that the agency says to expect the rain to give way to snow, "with a risk of brief freezing rain during the changeover."
Environment Canada warns that with the "much colder air moving in on Friday, icy conditions on roads and sidewalks are likely due to the freezing of residual water from either melted snow or rain."