Environment Canada issued a special weather statement for Toronto on Friday afternoon, expecting heavy rainfall that will hover over the city until Saturday evening. 

Rain is expected to begin tonight across the Greater Toronto Area as a weather system moves into southwestern Ontario. 

"The rain may fall heavy at times," the weather statement read. 

Between 25 to 40 millimetres of rain is expected to fall throughout the weekend, the federal weather agency says.

Environment Canada is calling for a low of 4 C tonight, but the temperature will climb to 7 C by morning.  A high of 9 C is forecasted for Saturday. 

The weekend rainfall is associated with a developing low pressure system that will cross the lower Great Lakes.