A hot and humid air mass began to warm up Montreal and its surrounding areas, including Laval, on Monday morning and will continue to do so throughout the day, according to Environment and Climate Change Canada (ECCC).
Temperatures are expected to reach 30 C but will feel hotter than 40 C with the humidity.
The ECCC said it could feel as hot as 43 C in highly urbanized areas and that temperatures will be “especially uncomfortable” there.
The federal department warned that health risks are greater for older adults, pregnant people, infants and young children, people with physical or mental illnesses and people with mobility issues or disabilities.
It advised Montrealers to seek a cool place and stay hydrated, even if they’re not thirsty, to decrease the risk of dehydration.
They should also watch for early signs of heat illness — including fatigue, thirst, and headaches — which could “rapidly evolve into life-threatening emergencies.”
Thunderstorms are expected to bring relief on Monday evening.