Heat warning issued for Ottawa as temperatures set to hit 36 C Tuesday

People cool off at the newly opened East Wharf Dock on Canada Day in Ottawa amid a heat warning on Wednesday, July 1, 2026. THE CANADIAN PRESS/Keito Newman

Environment Canada has issued a heat warning for Ottawa and eastern Ontario ahead of another hot and humid start to the work week.

The yellow warning – heat issued Sunday says daytime temperatures will range between 30 to 36 C starting on Monday with little relief in the evenings as lows stay between 20 to 23 C.

Daytime humidex values are expected to be between 38 to 45.

Tuesday will mark the peak of the heat event, with the high expected to hit 36 C in some areas. Temperatures are expected to return to normal by Thursday.

The five-day forecast shows mostly sunny skies, with a chance of rain and a risk of thunderstorms in the afternoon on Monday.

Smoke continues to linger

Environment Canada lifted an air quality warning issued for Ottawa and large parts of eastern Ontario on Sunday afternoon as wildfire smoke from Quebec wildfires began to dissipate towards the afternoon.

The forecaster says hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category. The forecast on firesmoke.ca shows mild levels of smoke lingering over the capital.

The air quality as of 3:30 p.m. was rated at 3 - low risk.

Quebec’s forest fire fighting agency (SOPFEU) is monitoring 182 active fires in northern Quebec and six in the southern “intensive protection zone.” An open fire ban is in effect for much of Quebec.

Environment Canada says extreme heat can be detrimental to one’s health, especially those at higher risk, including older adults and young children.

To protect from the heat, Environment Canada recommends:

• Drinking water often and before you feel thirsty to replace fluids.
• Closing blinds, or shades and opening windows if outside is cooler than inside.
• Turning on air conditioning, using a fan, or moving to a cooler area of your living space. If your living space is hot, move to a cool public space such as a cooling centre, community centre, library or shaded park.
• Follow the advice of your public health authorities.
• Planning and scheduling outdoor activities during the coolest parts of the day. Limit direct exposure to the sun and heat.
• Wearing lightweight, light-coloured, loose-fitting clothing and a wide-brimmed hat. Never leave people, especially children, or pets inside a parked vehicle.
• Checking the vehicle before locking to make sure no one is left behind. When there is an extreme heat event occurring with wildfire smoke, prioritize keeping cool.

Environment Canada says to be aware of the symptoms of heat stroke, which include red and hot skin, dizziness, nausea, confusion and change in consciousness.

With files from CTV News Ottawa’s Josh Pringle, William Eltherington and CTV News Montreal’s Daniel Rowe,