Caledon is in for one more stretch of steamy, storm-prone weather before a sharp change arrives, according to The Weather Network.
Warm, humid air will stay over Ontario through the end of the workweek, bringing additional rounds of showers and thunderstorms. Forecasters say Thursday afternoon brings more heat and humidity, along with a risk of isolated thunderstorms, particularly along a trailing trough and instability zone.
Eastern Ontario faces the greatest storm potential Thursday, though any activity is expected to remain scattered.
Overnight storm risk, then Friday's cold front
Overnight Thursday into the pre-dawn hours of Friday, storm complexes lifting from the U.S. Upper Great Lakes could affect parts of southern Ontario. The Weather Network cautions that confidence remains low on the timing and severity of these storms, but extreme southwestern Ontario carries the higher risk.
Temperatures in southwestern Ontario are hovering near heat warning thresholds, with major cities experiencing extreme conditions. Across southern Ontario, humidity is pushing humidex values into the mid to high 30s, with readings closer to the 40s in the southwest.
Friday brings a cold front as low pressure tracks through northeastern Ontario, raising thunderstorm risks in the east. Southern Ontario, including the Caledon area, is expected to stay dry and clear as the front sweeps out the humidity for the weekend.
Cooler, more comfortable air ahead
By Saturday, humidity levels will drop and temperatures should settle near seasonal values, offering a shift to more comfortable conditions for anyone heading outdoors.
The break won't last long. Another cold front is forecast to arrive late Saturday night into Sunday, bringing additional rain and thunderstorms. Behind it, brisk winds and cooler temperatures will settle in.
A significant pattern change follows. A deep trough over Ontario will push temperatures well below seasonal values by the start of next week, especially across northern areas of the province. Most of the coming week is expected to remain below seasonal averages.
For a June that has so far delivered above-seasonal warmth, the turnaround is notable. The Weather Network says no consistent heat is in sight after this week, and the pattern should remain unsettled at times into the final week of June.
That means residents should keep an eye on the sky through Friday, then dig out something warmer for the second half of the weekend and the week that follows.
