Kitchener-Waterloo

Isolated thunderstorms possible Thursday afternoon, Environment Canada says

Environment Canada says isolated thunderstorms could bring up to 25 mm of rain in some parts of the region and that could lead to ponding on streets and low-lying areas.

10 mm of rain likely in the region but storm could bring up to 25 mm in some areas

Ponding of water in low-lying areas is possible Thursday afternoon and evening, Environment Canada says in a special weather statement. (Kate Bueckert/CBC)

Isolated thunderstorms are possible in Waterloo region, Wellington County and Guelph Thursday afternoon and evening, Environment Canada said in a special weather statement.

The area could see general rainfall amounts of 10 mm, but "embedded isolated thunderstorms may boost local rainfall totals into the 15 to 25 mm range by late this evening," said the statement.

The special weather statement covers most of southern Ontario.

The ground is still frozen and snow-covered, which could mean the rain mixed with mild temperatures could cause "significant snowmelt or runoff."

That can lead to ponding on streets and low-lying areas, the statement said.

The Grand River Conservation Authority has issued a flood warning and watch for Thursday and Friday.

The GRCA predicts river flows to peak Friday in New Hamburg, Drayton and Grand Valley.

"There is the potential for ice jams in Grand Valley, New Hamburg, West Montrose, Brantford, Six Nations Territory, Cayuga and Port Maitland," GRCA said.