Heat and Humidity

Get notified of heat and other extreme weather warnings.

When the outdoor temperature and humidity are high, it can be hard for our bodies to keep cool and not overheat. Extreme heat events can cause sunburns, dehydration, heat exhaustion, heat stroke and in some cases, even death.

People at higher risk of getting sick from the heat include:

infants
older adults
pregnant people
people who work or exercise outdoors
people with pre-existing health conditions
people experiencing homelessness
people without access to air conditioning

Heat-related illnesses are preventable. Follow our tips below during a heat warning/advisory to help keep yourself and loved ones cool, safe and healthy.

Beat the Heat this Summer.

Prepare.

Wear a hat, light and loose-fitting clothing, sunscreen, and sunglasses when outside.
Bring a parasol, or an umbrella and water when leaving home in case you need to wait outdoors in the heat, such as in a lineup.
Keep your home cool by closing blinds and curtains on any windows facing the sun.
Drink plenty of water and avoid alcohol and caffeine.
Talk to your doctor, nurse, or pharmacist if you are taking medications, as some can make it harder to control body temperature.
Make sure to consult with your doctor if you are on a restricted fluid intake.
Discuss your health needs with your employer if your work demands will expose you to the heat.

A child wearing wide-brimmed hat and sunglasses, having sunscreen applied to nose.

Sun Safety

Protect your health by following our sun safety tips.

Learn more

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Being Prepared

Tips for building your emergency plan, and what to do when severe weather hits.

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Power Outages

Keep your food and water safe during a power outage.

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Take it easy.

Avoid unnecessary strenuous work or activity outside, especially between 10 and 4 p.m. If work must be done, take frequent water breaks in the shade.
If you're wearing a mask and undertaking physical exertion in the heat, a mask can make the effort more difficult. Lower the intensity and/or amount of work, and/or take more rests and cooling breaks if needed.
If you're breastfeeding, feed according to your child’s cues and drink plenty of water. Reach out to the nurses on our Family Health Information Line for more information on caring for your little ones during the heat.

Cool down!

Cool off in a public air-conditioned space such as the mall, library, or local community centre, in the shade, or at one of our district's public beaches, pools or splash pads.
Take cool baths and showers as often as needed, or soak hands and feet in cool water.
- If you cannot shower or bath easily, sponge often with cool wet towels. Focus on cooling the back of the neck, under the arms and groin area.
Open windows at night once the outdoor air is cooler than the indoor air; close windows in the morning before hotter air comes in.
Use fans at night to help exhaust warm indoor air and/or bring in cool outdoor air.
Use a fan and mist your skin with water.

More tips on fan use

DO...

Use your fan in or next to a window. Box fans are best.
Use a fan to bring in the cooler air from outside.
Use your fan by plugging it directly into the wall outlet.
If you need an extension cord, use one that is CSA (Canadian Standards Association) approved.

DON'T...

Don't use a fan to blow extremely hot air on yourself. This can cause heat exhaustion to happen faster.
Don't use a fan in a closed room without windows or doors open to the outside.
Don't believe that fans cool air. They don't. They just move the air around. Fans keep you cool by evaporating your sweat.

If you don’t have air conditioning, but have one or more large fans:

When the outside air is cooler than inside, use a fan in or next to a window to bring in the cooler air from outside, especially from a window on the shaded side of the building.
If a second fan is available, use it to blow air out of the home through a different window to help move cooler air throughout the home.
If you only have one fan but want cooler outside air to come in to more than one room, open windows in each of the rooms and use the fan to blow air out of a window in another room or hallway – air will be drawn into the home through the other open windows.
When it is hotter outside than inside, keep the windows closed and shaded and use a fan to blow air at yourself.
Drink lots of fluids so you perspire normally – the sweat evaporates more quickly with air moving over it to help cool you off.

This may not be enough when the humidity is very high, it is very hot, or your body doesn’t produce enough sweat. In these situations, you may have to seek a cool shelter.

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Beaches

Each summer, we sample the waters of local beaches to make sure they are safe for you to swim in.

Check the Status of your Local Beach

Stay connected, and care for others.

NEVER leave children, the elderly or pets unattended in a car, even with the windows open. The temperature will rise dangerously in only a few minutes.
Stay connected with people in your community who may have a difficult time coping with hot weather and those who live alone. Check on them often.
Keep in daily contact with friends and family to let them know how you are feeling. Ask for help if the hot weather is making you feel uncomfortable.
Listen to the radio for information about cooling stations, emergency reception centres and other guidance.
Watch for signs of sunburn, dehydration, heat exhaustion and heat stroke, and speak with your healthcare provider if you feel unwell.
For non-urgent medical advice, contact Health811.

Heat-Related Illnesses

Sunburn

Sunburn happens when skin cells that are not protected from direct exposure to the sun are burned. Depending on the length of the skin's exposure, the result can range from a mild burning sensation to severe blistering.

Research shows repeated overexposure to the sun may lead to various forms of cancer, including melanoma. Remember, there is no such thing as a healthy tan!

Children and people with fair or freckled skin, blue eyes, and light-coloured or reddish hair are generally more susceptible to sunburns.

Causes of Sunburn

Overexposure to the sun
Certain medications - talk to your pharmacist.

How to Prevent Sunburns

Stay in the shade and avoid the sun between 10 a.m. and 4 p.m., when the UV Index is 3 or higher . Keep in mind the sun's harmful rays can get through fog, haze and light cloud cover.

Do not apply sunscreen to babies under six months.

Wear a wide-brim hat, long sleeved shirts and pants.
Pay special attention around water, snow and concrete. They all reflect the sun and will intensify its effects.

Signs of Sunburn

Skin is red, tender and warm to touch
Blisters
Severe reactions such as fever, chills, nausea or rash
Peeling skin several days later

What to do if you have a sunburn

Severe sunburn requires medical attention. When in doubt, consult your health care provider.

Minimize pain and swelling with cool compresses, moistened washcloths that have been placed in the freezer, or take a cool bath.
Apply aloe gel if needed; avoid use of creams or lotions that can hold heat inside the skin or contain numbing medication (i.e. benzocaine or lidocaine).
Take a pain medication such as Tylenol™ or Advil™ to reduce pain and swelling.

Never give Aspirin™ (ASA) to children.

Dehydration

Severe dehydration can easily become a life-threatening condition for infants and the elderly.

Causes of Dehydration

Excessive loss of water and salts from the body due to severe sweating, illness, medication, or prolonged exposure to heat
Extreme heat
Diarrhea
Vomiting

How to Prevent Dehydration

Drink plenty of fluids throughout the day - more when sweating
Avoid strenuous work or sports activities during 10 a.m. to 4 p.m., when sunlight is most intense.

Signs of Dehydration

Thirst
Dry skin
Fatigue
Light headedness
Confusion
Dry mouth (mucous membranes)
Increased heart rate
Increased breathing rate
Less frequent urination

What to do if you're dehydrated

Move to a cool and dry place, if possible
Lie down and rest
Drink fluids such as water, juice or sports drinks. Do not drink alcoholic or caffeinated drinks.

Heat Exhaustion

Heat exhaustion is a non-life-threatening condition caused by the excessive loss of water and salts from the body due to prolonged exposure to extreme heat. City of Ottawa Paramedics remind you that continued exposure may lead to heat stroke, which is life-threatening. Young children and the elderly are most susceptible to heat exhaustion.

Causes of Heat Exhaustion

Prolonged exposure to extreme heat
Loss of body water and salts - usually through sweating
Not drinking enough fluids
Certain illnesses

How to Prevent Heat Exhaustion

Take frequent breaks when working or playing outdoors in extreme heat
Wear light-coloured clothes and a hat.
Avoid strenuous work, exercise or sports between 10 a.m. and 3 p.m., when the sunlight is most intense.
Drink plenty of fluids throughout the day, preferably water. 100% juice or sports drinks also help to keep you hydrated.

Signs of Heat Exhaustion

Headache
Blurred vision
Nausea or upset stomach
Vomiting
Sluggishness or fatigue
Thirst
Profuse sweating
Moderate increase in body temperature

What to do if experiencing heat exhaustion

Move to a cool and dry place, if possible
Lie down and rest
Apply cool water to skin and reapply often
Fan the wet skin
Drink fluids such as water, juice or sports drinks.
Apply ice to head, neck, armpits and groin areas
If showing signs of heat stroke, call 911 immediately.

Heat Stroke

Heat stroke is a life-threatening condition. Children, seniors, and people who work or exercise outdoors are most at-risk.

Cause

The internal (core) temperature of the body becomes too high, and the body cannot cool itself after after prolonged exposure to extreme heat.

How to Prevent Heat Stroke

Take frequent breaks when working or playing outdoors in extreme heat.
Wear light-coloured clothes and a hat.
Avoid strenuous work, exercise or sports between 10 a.m. and 4 p.m., when the sunlight is most intense.

Do not drink caffeinated drinks or alcoholic beverages.

Signs of Heat Stroke

Headache
Dizziness
Disorientation, agitation or confusion
Sluggishness or fatigue
Seizures
Hot dry skin
Increased body (inner) temperature
Loss of consciousness
Rapid heart beat
Hallucinations

What to do if someone has a heat stroke

Call 911 immediately.

Move the person to a cool and dry place
Apply cool water to skin and reapply often
Fan the wet skin
Apply ice to head, neck, armpits and groin areas

Clouds in sky

Air Quality

High air pollution and UV index levels often occur during hot weather conditions.

People with breathing and heart problems, and parents and caregivers of children, should pay attention to the hourly Air Quality Health Index.

Learn more