Overheated Ottawa under thunderstorm watch

Ottawa's hot summer hit a high on Thursday at 4 p.m., as temperatures rose to almost 36 C — the hottest mark of the year — and humidity made the heat feel more like 45.

Three city beaches remain open as humidex rises above 45

Ottawa's hot summer hit a high on Thursday, as temperatures rose to 35.8 C at 4 p.m. — the hottest mark of the year — and humidity made the heat feel more like 45.

City crews on Bank Street stopped road work as the temperatures rose and an oppressive wave of heat engulfed much of the downtown core.

Environment Canada issued a weather warning cautioning people in the region of high humidity and the City of Ottawa has issued a heat warning for the day.

The highest recorded temperature for Ottawa on July 21 was 36.7 C, recorded in 1955.

Environment Canada also issued a severe thunderstorm watch for the National Capital Region and the surrounding area, saying the afternoon has the potential to bring damaging winds, heavy rain or hail to the region.

The possibility of thunderstorms was unwelcome news in a region where thousands lost power — some for days — after a severe windstorm on Sunday brought down trees and tree branches.

Heat warning in effect

The city's medical officer of health, Dr. Isra Levy, issued a heat warning on Wednesday, saying extreme heat can cause dehydration, heat exhaustion, heat stroke and even death. He said infants, young children, the elderly, the chronically ill, and the homeless are at greater risk from extreme heat.

The heat warning is automatically declared when Environment Canada forecasts a humidex of 40 C or more for at least two consecutive days.

Soccer matches in west Quebec were also cancelled Thursday because of extreme heat, according to Marc St-Amour, the competition director for the governing body for both the Regional Outaouais Soccer League (LRSO) and the Outaouais Senior Soccer League (LSSO).

Two schools in Ottawa are closed Thursday because of the hot weather. The Adult High School on Rochester Street, and Immaculata High School on Main Street are not fully air-conditioned. Classes will resume on Friday.

The city announced that Petrie East Bay and Mooney's Bay beaches were under no-swim advisories because of high e.coli levels. Westboro, Britannia and Petrie River beaches were open to swimmers.