More than 200 weather and air quality alerts are currently active across Canada this weekend, with extreme heat warnings issued for large parts of Ontario and Quebec.
Key highlights:
Extreme Heat Warnings
The first major heat wave of the season is forecast to begin Sunday afternoon and continue into the week, bringing dangerously high temperatures and humidity.
As of Sunday morning, a widespread heat warning is in place covering southern Ontario and Quebec—from Sault Ste. Marie in the west, down to Windsor in the south, north to Val-d’Or, and east to Sherbrooke.
In these areas, daytime highs are expected to reach between 31 and 36°C, with humidex values at or above 40. Overnight temperatures will only drop to the high teens or low-to-mid 20s, offering minimal relief from the heat.
A special weather statement has also been issued for the Quebec City area and regions stretching north from La Tuque toward Lac Saint-Jean, where humidex values near 40 are expected.
In addition, areas along Ontario’s southern border with Minnesota are under a heat warning through late Sunday, with daytime highs of 28 to 30°C, overnight lows near 18°C, and high humidity.
Further west, parts of northwestern Yukon are experiencing a prolonged stretch of elevated temperatures, with daytime highs forecast in the mid to high 20s.
Safety Recommendations
Residents in affected regions are urged to take precautions to stay cool and safe. Recommendations include:
- Drinking plenty of water
- Staying in air-conditioned or shaded areas
- Using fans or ice packs
- Visiting local cooling centres
Environment Canada warns of heat-related symptoms such as:
- Headaches
- Dizziness
- Nausea
- Thirst
- Dark urine
- Severe fatigue
More serious signs, including confusion, hot red skin, or altered consciousness, may indicate heat stroke, a medical emergency. In such cases, call 911 immediately and begin cooling measures—such as removing excess clothing, applying ice packs or cold water, and relocating the person to a cooler environment.
