Heat Warnings in Markham

Stay cool. Stay hydrated.

Environment & Climate Change Canada issues Heat Warnings across Canada.

A Heat Warning is issued when there is a forecast of two or more consecutive days with daytime maximum temperatures of 31°C (87.8°F) or warmer, together with nighttime minimum temperatures of 20°C (68°F) or warmer or when there is a forecast of two or more consecutive days with humidex values expected to reach 40°C (104°F) or higher.

How you can stay safe

  • Drink plenty of cool liquids, especially water, to decrease your risk of dehydration

  • Frequently call to check in with friends, neighbours, and elderly family members, especially those who are chronically ill, to make sure they are cool and hydrated

  • Call and check in on friends, family members, and neighbours who may be living in a building without air conditioning (it is especially important if they are elderly)

  • Reschedule or plan outdoor activities during cooler parts of the day or avoid outdoor activities if you have health concerns

  • Keep people and pets in your care out of parked vehicles and direct sunlight

  • Spend a few hours in a cool place while practicing physical distancing, such as a tree-shaded area

  • Wear loose-fitting, light-coloured clothing made of breathable fabric and ensure you wear a hat and sunglasses

  • Avoid sun exposure – shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella

  • Take cool showers or baths

  • Prepare meals that don't need to be cooked in your oven

  • Block sunlight by opening awnings, and closing curtains and blinds during the day

  • If you are taking medication or have an existing health condition, ask your doctor or pharmacist if heat exposure increases your health risk and follow their advice

  • If you have an air conditioner with a thermostat, keep it set to somewhere between 22ºC (72ºF) and 26ºC (79ºF), which will reduce your energy costs and provide you with needed relief

  • If you have a window air conditioner, cool only one room where you can go for heat relief

Heat-related illness

Extreme heat is a health risk and heat-related illness is preventable. Watch for the symptoms of heat illness:

  • Dizziness and fainting

  • Nausea and vomiting

  • Rapid breathing and heartbeat

  • Extreme thirst

  • Decreased urination with unusually dark urine

If you experience any of these symptoms, immediately move to a cool place and drink liquids. Cool water is best, not ice cold liquid.

Heat stroke is a medical emergency. Call 9-1-1 if you have or someone you are with has a high body temperature, along with one or a combination of the following: confused, unconscious, or has stopped sweating.

While you are waiting for help, cool the person right away by moving them to a cool or shady place, remove excess clothing, and/or applying cool water to large areas of the skin or clothing.

Be Notified of Heat Warnings

Check Environment & Climate Change Canada website for information on your local forecast and weather alerts or download their mobile app, WeatherCAN, which provides weather alert notifications in your area, as well as in your saved locations.

During a heat warning, residents are reminded to stay cool and hydrated, keep people and pets out of parked vehicles and to check on elderly persons.

It is important to take precautions to avoid suffering heat-related illnesses.

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