Extreme heat warning issued for Ottawa ahead of Canada Day

CTV’s Jackie Perez shares the full local 6 p.m. forecast for Tuesday, June 30, 2026.

It’s going to be a sweltering Canada Day in the nation’s capital.

Environment Canada issued an orange warning – heat for Ottawa in advance of a “long duration heat event” expected to begin on Wednesday.

“The hottest days are expected to be Wednesday and Thursday, with maximum temperatures up to 35 degrees Celsius expected. Minimum temperatures of 21 to 25 degrees Celsius will provide little relief from the heat,” Environment Canada’s warning says.

Hot and humid air may deteriorate the air quality.

A yellow-level severe thunderstorm watch is also in effect on Tuesday in Ottawa, with conditions being favourable for the development of severe thunderstorms that may be capable of producing strong wind gusts, large hail and heavy rain.  

Environment Canada says risks include wind gusts of up to 110 km/h, golf ball-sized hail, rainfall amounts in excess of 50 millimetres, and possible tornadoes.

A tornado warning in the Kingston area issued earlier in the afternoon has been lifted.

The orange level on Environment Canada’s colour-coded scale refers to weather that is likely to cause significant damage, disruption or health impacts. Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

The less severe yellow warning refers to impacts that are moderate, localized and/or short-term.

The City of Ottawa says it will be opening some of its facilities on Canada Day to help residents cool off from the heat.

Ottawa City Hall will be open from 8 a.m. to 8 p.m. and Ben Franklin Place in Centrepointe will be open from 8 a.m. to 9 p.m. Other open facilities and hours are available online.

Environment Canada recommends taking steps to protect yourself and vulnerable individuals from the heat.

“Determine if you or others around you are at greater risk of heat illness. Check on older adults, those living alone and other at-risk people in-person or on the phone multiple times a day,” Environment Canada says.

Environment Canada also recommends:

• Drinking water often and before you feel thirsty to replace fluids.
• Closing blinds, or shades and open 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.
• Following the advice of your region’s public health authority.
• Planning and scheduling outdoor activities during the coolest parts of the day.
• Limiting direct exposure to the sun and heat. Wear lightweight, light-coloured, loose-fitting clothing and a wide-brimmed hat.
• Never leave people, especially children, or pets inside a parked vehicle. Check the vehicle before locking to make sure no one is left behind.

The hottest Canada Day on record in Ottawa was recorded in 1931 with a temperature of 37.2 C.

Ottawa weather

Environment Canada’s weather forecast for Ottawa calls for showers ending early on Tuesday then partly cloudy with a 40 per cent chance of showers.

Overnight, expect little relief from the heat, with a low of 23 C, around eight degrees warmer than the average low for this time of year.

Canada Day could see a high of 36 C with a humidex of 47. The forecast includes a mix of sun and cloud and a 40 per cent chance of showers in the afternoon with risk of a thunderstorm.

The heat continues on Thursday with another high of 33 C, and a 40 per cent chance of showers.

Friday’s forecast includes a high of 33 C and a 30 per cent chance of showers.

The weekend still has highs around 30 C, but the heatwave should break by Monday.

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