WATERLOO -- Note: Environment Canada ended the heat warning for Waterloo Region and surrounding areas at 4:45 a.m. Tuesday.

A heat warning was issued by Environment Canada for Waterloo Region as well as Guelph, Erin, and Southern Wellington County.

The statement issued on Sunday came into effect just before 5:30 a.m.

The heat event will continued through Monday, and ended early Tuesday morning.

Maximum temperatures for the area on Monday were expected to be around 32 degrees Celsius with a humidex of up to 41.

Minimum overnight temperatures were expected to be around 20-23 degrees.

The high temperatures are leading to a rise in customers at some local outdoor businesses.

Tubing the Grand owner Gary Gerger says they are sold out for the summer.

“We actually have people show up at our launch site that don’t have a reservation thinking that they’re going to be able to go, but that’s just not the way it works this year,” says Berger.

Shelly Jo Holmes with Canoeing the Grand says due to the COVID-19 pandemic the outdoor activity season did start is many unknowns.

“We already suffer when we’re seasonal. It was a scary start, wasn’t sure if we were going to open,” says Holmes.

Holmes says thankfully due to the weather so far customers have been able to appreciate the ability to stay distanced from each other in the fresh air.

“We have this beautiful river and I am so glad that people from all over Ontario are discovering it as we break out of our prisons,” says Holmes.

Environment Canada is warning that young children, pregnant women, older adults, people with chronic illnesses, or people exercising outdoors are a greater risk during extreme heat.

High heat also came to Toronto, London, Windsor, and their surrounding areas as well on Sunday.