Temperatures approaching 40C without humidex today & tomorrow across the Prairies, before a cold front moves through, bringing thunderstorms in the forecast. Risk of severe weather across SE Manitoba and NW Ontario. Areas near Kenora and along the Trans-Canada Highway should be on the lookout for supercells on Friday.
But first, the heat
National Blend of Models (NBM) showing temperatures near 35C without humidex across Saskatchewan & Alberta as daytime highs today.
No relief from the heat tomorrow as temperatures approach the 40C mark ahead of a cold front sweeping through Manitoba.
Heat warnings have been issued by Environment Canada already:
4:44 AM CDT Thursday 03 June 2021 Heat Warning in effect for areas in red:
Very hot temperatures are pushing their way through southern Manitoba from the west. Temperatures will rise into the low thirties for Thursday and will be extremely hot Friday and Saturday. Overnight lows will be in the teens. Humidity will remain low for the next couple of days, with higher humidity likely for Saturday. Temperatures may fall just short of our usual warning criteria in some areas Thursday. However, given the added concerns these days with COVID-19 and associated precautionary measures, the warning criteria has been relaxed slightly. Everyone is at risk for the effects of heat. However, during a period of prolonged heat, older adults, people with chronic illness and people living alone have a particularly high risk for heat illness, especially if they are living in an urban area or do not have air conditioning. Others at greater health risk to heat include infants and young children, and people who work or exercise in the heat. Take care of yourself and others. Ensure you check in regularly with vulnerable or socially isolated community members, friends and family. Contact people by phone where possible to reduce face-to-face interactions, which will help control the spread of COVID-19. Never leave people or pets alone in a parked vehicle or direct sunlight, and be sure to provide water.
Then comes the storms
Severe storms are expected along the MB/ON border tomorrow afternoon.
Discussion: a large warm sector will bring very warm temperatures across S MB/NW ON on Friday. A cap, will prevent thunderstorms from developing until early afternoon along the cold front. This should result in explosive supercell development near the MB/ON border along the Trans-Canada Highway. Supercell modes are expected to remain discrete in their early life-cycle and quickly transition to MCS. This convective complex should move east along the Trans-Canada towards Thunder Bay, eventually losing intensity with lost of daytime heating. Tornadoes will be possible between the hours of 1pm CDT to 5pm CDT while storms remain discrete, especially in an area along and south of Kenora.
Above shows a satellite model simulation of the MCS along the Trans-Canada Highway tomorrow in the late-afternoon.