High temperatures are in the forecast for southern parts of the region closest to the Minnesota border.
A heat warning is out for the Kakabeka Falls area, Atikokan, Shebandowan, and Quetico Park west to Fort Frances and Rainy Lake.
Hot and humid air is pushing the temperature to near 30 degrees today, and near 18 degrees overnight.
Environment Canada predicts the weather will cool down slightly tomorrow.