This long weekend starts a heat wave that will stretch across most of North America. For at least the next ten days temperatures will be 5-10 degrees above normal with insufferable humidity. Humidex values could reach above 40°C which could cause fainting, heat exhaustion, and heat stroke.
Overnight temperatures will provide little relief with temperatures near 20°C, but high relative humidity will make it feel close to 30°C. There is some brief relief on Sunday with rain, but temperatures remain well above normal that day and well into next week.
All of this extreme heat and moisture provide the ingredients for strong thunderstorms. Thunderstorm activity will be scattered and difficult to predict, but some storms may become severe with damaging winds and hail.
Friday will see early morning thundershowers give way to partly cloudy skies today. Warm, muggy conditions move into the region with daytime highs will be near 31°C, but increased humidity will make it feel more like 38°C. There is the risk of scattered thunderstorms in the evening and overnight. Winds will be southerly at 10-15km/h.
Saturday starts out again with the risk of thunderstorms followed by a mix of sun and cloud. Temperatures will climb to near 33°C, but it will feel more like 43°C with the humidity! A southwest breeze of 10-15km/h will blow in the afternoon. The risk of scattered thunderstorms returns in the evening and overnight.
The unsettled muggy weather will continue for Sunday with the chance of rain and storms through the day. Daytime highs will climb again into the low 30s, but the humidex values will be about 10 degrees warmer. Southerly winds early in the day will trend to the west later in the day.
Monday may start out cloudy, but sunshine moves in through the day with temperatures still near 30°C. Winds will be westerly and provide cooler temperatures north of the city along the Eastern Superior shores.
Temperatures continue in the low 30s well into next week and possibly next weekend.