Environment Canada issued a heat warning with temperatures hitting between 29 and 33 C from Tuesday through to Wednesday -- with cooler temperatures expected for Thursday.
As the sun's searing rays were beating down, families were looking to snatch up what little shade was available at the Lake Nipissing waterfront.
"Well that's exactly what we tried to do,” said one woman sitting comfortably in the shade.
“Come and look for the shadiest spot."
It’s not just families trying to stay cool. The first few of the yearly shad flies huddled together in the shade on the side of buildings, seeking refuge from the sun.
"My granddaughter and I are having a good time,” said one grandmother, spending time with her granddaughter at Shabogesic Beach Park.
“We bring drinks, we bring whatever we might need. She has her bathing suit if she wants to change."
North Bay opened cooling facilities for anyone who needed to cool down, including Memorial Gardens (sections 1, 2, 5 and 7) until 4 p.m., Pete Palangio Arena until 11 p.m. and transit terminal on Oak Street until 4:30 p.m.
“We've put on our air conditioners and closed all of our curtains and we've decided to come for a walk in the breeze before it becomes too stifling,” one couple said.
“The risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors,” Environment Canada said.
People are being advised to keep an eye out for the effects of heat illness, which may include swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions.
Senior climatologist Dave Phillips said heat warnings are in effect across Ontario.
While areas near the lakes could be slightly cooler than regions further inland, hot and humid air can still bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.
"That's why we have heat warnings from Wawa to Windsor. From to Moosonee to Mississauga," Phillips said.
Humid temperatures have forced staff to close the Heritage Railway and Carousel Company tourist attraction. Staff are hoping to reopen Thursday pending the weather.
"For the safety of not only of the people who come and ride the train, but for our volunteers, many of them are over 65 and have health conditions,” said treasurer Don Coutts.
- Download the CTV News app now and get local alerts on your device
- Get local breaking news and updates sent to your email inbox
The North Bay Parry Sound District Health Unit is encouraging people to dress in light, loose clothes, wear a hat and sunglasses, drink plenty of water and, of course, apply sunscreen with at least an SPF 30 to your skin.
"Heat stroke, heat exhaustion, and dehydration share a lot of similar symptoms like nausea, confusion, and decreased urination,” said the health unit’s Quintin McCluskie.