Heat warning extended through Saturday as Ontario battles extreme humidity and dangerous temperatures
Environment Canada's orange heat warning continues across Ontario this weekend as the province experiences temperatures near 40°C and dangerous humidity levels.
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Ontario residents are facing an extended heat warning through Saturday as the province battles extreme temperatures and humidity that pose significant health risks.
A new report from the Canadian Climate Institute reveals climate change is making heat waves more frequent, longer-lasting and more intense. Long-lasting heat waves have become nearly three times more common than they were in the 1950s, driven by stalling weather patterns that trap hot air over large regions — what researchers call a "heat dome."
Canada is warming twice as fast as the global average, while the Arctic is warming nearly four times faster due to its geography and shrinking snow and ice cover. This stronger baseline means extreme heat events reach greater heights and affect larger areas.
These more frequent heat waves come with significant health risks, particularly for seniors, children, pregnant people and those with pre-existing conditions. Repeated heat exposure can age the body in ways comparable to smoking, putting physical stress on the entire system. Symptoms include rashes, cramps, edema, fainting, fatigue and heat stroke.
Environment Canada advises residents to drink plenty of water, close blinds, limit direct daytime exposure between 11 a.m. and 3 p.m., and check on vulnerable friends and neighbours.
