Heat warning in effect for Greater Sudbury until Thursday
OTTAWA, Monday, July 14, 2025 – 15:50 EDT — Environment Canada has issued a heat warning for Greater Sudbury and vicinity, as a sweltering heat wave is forecast to intensify from Tuesday through Thursday. Daytime temperatures will soar, with highs expected between 28°C and 31°C (82°F to 88°F), while the humidex could push the perceived temperature up to 38°C (100°F).
Overnight lows will remain elevated as well, staying between 19°C and 23°C (66°F to 73°F), offering minimal relief during the night and increasing the risk of heat-related stress.
What to expect in Greater Sudbury
Residents across Greater Sudbury, from the downtown core to outlying communities, should brace for oppressive heat and high humidity through at least Wednesday, with a slightly cooler air mass expected to bring some respite by Thursday.
Persistent heat during both the day and night increases the risk of heat exhaustion and heat stroke, especially for older adults, children, and those with pre-existing health conditions.
Although a cooler air mass is expected by Thursday, Tuesday and Wednesday will remain particularly hazardous due to the sustained high temperatures, moisture levels, and lack of nighttime cooling.
Humidity and high heat expected to peak mid-week
This weather event will push the humidex values toward the upper 30s, creating intensely uncomfortable conditions, especially for those without adequate cooling. Local authorities continue to advise the public to monitor forecasts and take appropriate precautions.
Extreme heat episodes like this have the potential to affect not just vulnerable groups, but anyone spending prolonged periods outdoors in direct sunlight, or those working in unventilated indoor environments without air conditioning.
Stay updated with further heat advisories from Environment Canada and be aware that heat-related illnesses can set in quickly, even during seemingly moderate physical activity.
For more updates and regional warnings, continue to follow Environment Canada and regional public health bulletins.
