The mild weather in Waterloo region will be short-lived, as more cold weather and icy conditions are expected hit southern Ontario.

Environment Canada has put Waterloo region and Wellington County under a special weather statement due to rainy conditions that will be quickly followed by a return of the winter weather.

"With 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," said the national weather agency in a statement released Thursday morning.

Mild and rainy conditions are expected most of Thursday in southern Ontario and into Friday, with 10 to 20 millimetres likely in most areas.

The mild temperatures will abruptly end on Friday with a strong cold front moving across the region. Environment Canada said in a stament the rain will quickly transition to snow, with a risk of freezing rain. The snowfall will only be a few centimetres on Friday.

The rain and melting snow may result in pooling water on roads and flooding in the region, said the statement.

The Grand River Conservation Authority has also issued a flood watch for the entire Grand River watershed.

GRCA said in a statement Wednesday night, there will be an elevated risk of flooding for low-lying areas along the Grand, Speed, Nith and Conestogo rivers, and other connected waterways, until Friday afternoon when temperatures drop.