Several regions in southern Ontario were under heat warnings for the third consecutive day Thursday — with sweltering conditions expected to last into Friday or Saturday.
Environment Canada said affected regions included Toronto, Hamilton and Halton, as well as Sarnia and Windsor.
Much of the province has been experiencing scorching weather this week, with daytime temperatures in the low 30s, or upper 30s with humidity.
Forecasts call for temperatures to feel closer to 40 C with humidity in Windsor over the next four days, with slightly cooler temperatures expected on Sunday.
The weather agency has said expected overnight lows near 20 C in most regions will provide little relief from the heat.
Parts of northern Ontario also experienced heat warnings earlier in the week.