It’s not often the weather is described as dangerous, but this is one of those weeks.

A heat warning is in effect for an area that includes the GTA and Ottawa, stretching west to Sault Ste. Marie and as far north as Fort Albany.

Not just Monday, but every day through Friday, high temperatures will be in the low 30s with humidity making it feel in the low to mid 40s.

The heat warning from Environment Canada notes the health risks associated with heat illness are greater for older adults, infants and young children and other vulnerable groups.

To help ensure the safety and wellbeing of all residents during the summer season, the City of Toronto activates its Heat Relief Strategy from May 15th to September 30th each year.

A key part of the strategy is the Heat Relief Network where people can access Cool Spaces across the city including libraries, community centres and pools, to seek relief from summer heat.

Sunday, the City’s 10 wading pools and 10 outdoor pools opened ahead of schedule to provide residents with more options for staying cool during hot weather.

For more information, including pool hours, visit the City’s Swimming & Water Play webpage.

The City of Toronto is also offering these tips to stay cool:

– Stay hydrated. Drink water regularly, even when not thirsty.
– Plan outdoor activities for cooler times of the day.
– Seek shade or use an umbrella to avoid direct sun exposure.
– Use a fan to circulate cool air indoors when the temperature is below 35 degrees Celsius.
– Keep blinds or curtains closed during the day to block out the sun.
– Wear lightweight, loose-fitting clothing and wide-brimmed hats outdoors.
– Take cool showers or use cool, wet towels to cool down.
– In an emergency, always call 911.

The hot air will move eastward later in the week. Temperatures on the weekend will be in the mid to high 20s.