Feeling like 50: Hottest temperatures of the year coming to southern Canada

An incoming heat dome is set to bring sweltering temperatures and high humidity to parts of Canada

This weekend, parts of southern Canada will experience some of the warmest conditions of the year as a U.S. heat dome strengthens and spreads north.

High temperatures, combined with elevated humidity, will push humidex values to dangerous levels, exceeding 40 in many areas.

Baron - National temperature pattern this weekend - July 10

In the southern Prairies, the heat begins Saturday, with southern Saskatchewan and Manitoba expecting the highest temperatures on Sunday. Daytime highs could reach the mid to high 30s in provinces like southern Manitoba and southern Saskatchewan, while southern Alberta will see highs in the low 30s.

Winnipeg could reach 36°C with a humidex of 46 on Sunday, climbing to 37°C (humidex 45) Monday—potentially marking the city’s hottest day since August 2018.

Baron - Winnipeg heat stat - July 2026

Temperatures in these regions are forecast to be more than 10°C above seasonal norms, which typically hover in the mid-20°C range.

The heat will expand eastward into Ontario and parts of Quebec early next week. By Tuesday, areas like Toronto, Ottawa, Montreal, and their surroundings could experience humidex values around 40.

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Baron - Ontario humidex weekend - July 10

Northern and eastern Ontario, including Thunder Bay and Timmins, will also reach the 30s, with high humidity making conditions feel even warmer.

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A slight break from the heat is expected by midweek. However, elevated heat-related illnesses remain a risk during this period. Additionally, thunderstorms may develop along the periphery of the heat dome in a "ring-of-fire" pattern.

Hot weather safety tips:

  • Drink plenty of water. Avoid caffeine and alcohol, which can be dehydrating.

  • Avoid direct sunlight, especially during peak hours and when the UV rating is high.

  • Wear lightweight, loose-fitting clothing.

  • Use air conditioning when possible. If you do not have access to air conditioning, consider visiting a cooling centre, a shopping centre, or a public library.

  • Check on elderly relatives and other vulnerable neighbors.

  • Avoid strenuous activities during the hottest parts of the day.

  • If you experience symptoms of heat-related illnesses like dizziness, nausea, or confusion, seek medical attention.

Explainer: Heat Stroke, heat exhaustion symptoms, health, heat wave

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