Southern Manitoba could see a touch of frost overnight, a reminder that summer is winding down as students prepare to return to school next week. Frost risk tonight only Environment Canada is calling for clear skies tonight with temperatures dropping to 4 C. With light winds expected overnight, forecasters say there is a risk of frost developing in low-lying areas. Fog patches could also form. The chilly temperatures will be short-lived. By Monday afternoon, the forecast calls for sunshine and a high of 23 C, with overnight lows around 9 C. Warmer week ahead The rest of the week is expected to feel more like summer. Highs will reach the mid-20s from Tuesday through Friday, with daytime temperatures peaking at 27 C to wrap up the week. Overnight lows are forecast to stay between 11 C and 12 C. Long weekend outlook With the September long weekend just ahead, weather conditions appear favourable for outdoor plans. No further frost risks are in the forecast, and skies are expected to stay mainly sunny.