Thursday, September 19th 2019, 8:30 am - Surging late-summer heat will threaten temperature records for parts of Ontario.
A ridge of high pressure has begun to steer heat and humidity from the southern U.S. back into Ontario for the second half of the week, and that may leave some new record highs in its wake. After a toasty Wednesday in the north, the south will follow closely behind as humidex values climb into the mid-30s into the weekend. We track the heat, where records might fall and when the remnant tropical moisture from Imelda puts an end to this sunny streak, below.
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- Temperatures rise into latter half of week
- Mid-30s humidex values likely for south by weekend
- Cooler temperatures arrive with fall on Monday
WATCH BELOW: TRACKING THE RIDGE
A strong ridge of high pressure stretching from the Maritimes to the Gulf Coast served as a conveyor belt of warm air aimed right at northern Ontario for Wednesday, where above-average temperatures were the norm.
The south was also warm Wednesday, with more of the same ahead for Thursday. Daytime highs in the low-to-mid 20s will feel slightly warmer with the humidity.
That warmth will only continue to build as the main axis of the ridge shifts east to close out the work week, putting the main push of heat and humidity into southern Ontario.
Temperatures feeling like the mid-to-upper 30s will have those in southern Ontario firing up the air conditioner again beginning on Friday, with the heat expected to peak on Saturday.
The last few days of summer will feature humidex values more appropriate for late-July than late-September.