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Severe Weather Alerts - Oldcastle, Ontario

  • Heat Warning

    Heat Warning in effect until 8:33 PM EDT. Source: Environment Canada

Hot and humid today into the weekend.

Significant heat and humidity are on tap today and Saturday with afternoon temperatures in the mid thirties and humidex values in the mid to possibly upper forties. This mid summer sizzler may result in the highest temperatures so far this year.

A cooler and less humid air mass is forecast to arrive in the wake of a weak cold front beginning on Sunday finally providing relief from the heat.


Extreme heat affects everyone.

The risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors.

Watch for the effects of heat illness: swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to or tweet reports using #ONStorm.