After days of sweltering heat, parts of southern Ontario are getting a soaking as rain clouds and isolated thunderstorms rumble across the province Friday.

In a special weather statement, Environment Canada said some of the slow-moving storms could produce heavy rain with amounts of 40 millimetres or more, giving the Canada Day weekend a soggy start.

Environment Canada is warning motorists to be prepared for low visibility and poor driving conditions, including pooling on roads, in heavy downpours.

In Toronto, pooling occurred on parts of Lake Shore Boulevard and the Gardiner Expressway, and near Allen Road and Sheppard Avenue West.

Rain is expected to continue through the day and the afternoon high is expected to be 21 C, as temperatures dip below seasonal for a few days.

Environment Canada is predicting more rain Saturday, along with a high of 23 C.

Sunday and Monday are expected to be dry, with a high of 25 C and a mix of sun and cloud, as the long weekend comes to a close.

Normal temperatures for this time of year are highs of 26 C and lows of 15 C.

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