Ottawa residents who've enjoyed a brief break from the summer swelter should get ready to sweat again — hot and humid weather is expected to return to the capital this Sunday, according to CTV News.
What to Expect
After a stretch of more comfortable conditions, Environment Canada's typical summer pattern for the region points to rising temperatures and climbing humidity levels moving into the weekend. For Ottawa, that combination often means humidex values that feel several degrees warmer than the actual air temperature, especially during the afternoon hours when the sun is at its strongest.
Locals know the drill by now: when the humidity rolls in off the Ottawa River and settles over the city, even a modest temperature reading can feel oppressive. The National Capital Region's mix of urban heat and nearby waterways tends to amplify that muggy, sticky feeling that keeps window air conditioners humming from Barrhaven to Orleans.
Why Ottawa Feels It More
Ottawa's geography plays a role here. Sitting at the confluence of the Ottawa, Rideau, and Gatineau rivers, the city often experiences higher humidity than other parts of Eastern Ontario during summer heat events. That moisture, combined with the concrete and asphalt of the downtown core, can make neighbourhoods like the ByWard Market or Centretown feel noticeably warmer than the official forecast temperature suggests.
For anyone with outdoor weekend plans — whether it's a stroll along the Rideau Canal, a visit to one of the city's many patios, or a trip to the beach at Mooney's Bay — it's worth planning around the hottest part of the day, typically early-to-mid afternoon.
Staying Safe and Comfortable
With the heat and humidity set to climb, Ottawa Public Health's standard advice applies: stay hydrated, seek shade or air-conditioned spaces during peak heat, and check in on elderly neighbours or those without reliable air conditioning. The City of Ottawa also operates cooling stations at select community centres and libraries during periods of extreme heat, a resource worth keeping in mind if temperatures spike further.
Pet owners are also reminded to keep walks shorter and scheduled for cooler parts of the day, and to never leave animals in parked vehicles, even briefly, when humidity is high.
The Bigger Picture
This kind of back-and-forth between milder stretches and sudden humid spikes has become a familiar rhythm for Ottawa summers in recent years. Whether you're headed to a festival on the LeBreton Flats or just trying to get through a Sunday errand run, it's a good reminder that the capital's weather can turn muggy fast — so keeping the sunscreen, water bottle, and light clothing within reach this weekend is a smart move.
Source: CTV News
