Environment Canada has issued a special weather statement for Toronto, saying "significant "rainfall is expected on Sunday.

Between 25 millimetres to 40 millimetres of rain is possible, the federal weather agency said in the statement.

Environment Canada said a low pressure system that developed over the western U.S. is making its way over Southern Ontario.

"The rain may fall heavily at times but there may also be significant breaks in precipitation," the statement read. "Some thunderstorm activity is also possible."

The amount of rain in many areas could be "appreciable," it said.

The wet weather is expected to taper off early Monday.