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Preparing for Heat Events

Here you will find information on preparing for heat events and what to know about the different types of heat alerts.

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Heat events, also known as heatwaves, are a series of days that are hotter than normal temperatures for the region. As the climate changes, heat events will become more frequent, longer, and hotter in British Columbia.

Heat events can affect anyone's health, but extreme heat can pose a very high risk of severe illness for some people if they do not have access to a cool indoor environment. Heat can build up indoors when the outdoor temperatures are climbing every day, and the situation can become dangerous. The longer the heat lasts, the more dangerous it becomes.

Indoor heat can be dangerous, especially if the temperatures stay over 31C for long periods. If you are at risk and it gets very hot in your home during extreme heat events, plan to go somewhere cooler during an extreme heat emergency if possible.

Extreme Heat Preparedness Guide - link goes to BC Government web pageOn this page

  1. Understanding heat alerts
  2. Heat warnings
  3. Heat emergencies
  4. Who is at higher risk from heat
  5. Prepare before extreme heat
  6. During heat events
  7. Know the signs of heat illness

Understanding heat alerts

There are two types of heat alerts in B.C. These heat alerts come from Environment and Climate Change Canada.

Check for heat alerts

Heat warning

This means daytime and overnight temperatures are higher than usual, but they are not getting hotter every day. Take the usual steps to stay cool.

Video: What is a Heat Warning?

Extreme Heat Emergency

Daytime and overnight temperatures are higher than usual, and they are getting hotter every day. Activate your emergency plan.

Video: What is a Heat Emergency?

Who is at higher risk from heat?

Some people are at greater risk:

  • Seniors aged 65 years or older
  • People who live alone or who are socially isolated
  • People with mental illnesses such as schizophrenia, depression, or anxiety
  • People with chronic health conditions such as diabetes, heart disease or respiratory disease
  • People who have a disability
  • People with limited mobility
  • People with cognitive impairment
  • People with substance use disorders
  • People who do not have access to adequate housing
  • People who work in hot environments (such as kitchens, or outside)
  • Pregnant people
  • Infants and young children

Prepare before extreme heat

Prepare for the upcoming conditions before the heat starts.

  • Identify a cooler space in your home and prepare it so you can stay there at night, if possible. You may need to change daily living arrangements
  • Find an air-conditioned spot close by where you can cool off on very hot days. Consider staying with friends or family or find places in your community to spend time such as movie theatres, libraries, community centres, or shopping malls
  • Check that you have a working fan. If you have an air conditioner, make sure it works
  • Install awnings, shutters, blinds, or curtains over your windows to keep the sun out during the day
  • Practice opening doors and windows to move cool air in at night and shutting windows during the day to prevent hot outdoor air from coming inside
  • Get a digital room thermometer to keep with you so you know when your home is getting too hot
  • Think of people you know who may be more susceptible to heat and develop a buddy system
  • Check in with your hot weather buddy often, especially in the evening when indoor temperatures are highest. It is also good to check early morning, to see how your buddy has managed through the night
  • If your home is cooler, invite those who are at highest risk to stay with you
  • If you take regular medications, drugs, or have a health condition, ask your doctor or pharmacist whether it increases your health risk in the heat and follow their recommendations
  • Know the signs and symptoms of heat-related illness so you can identify problems early on. Severe headache, confusion, unsteadiness, loss of thirst, nausea/vomiting, and dark urine or no urine are signs of dangerous heat-related illness

During heat events

  • Check on people at higher risk in-person to evaluate their health and the temperature indoors. If you cannot check in-person, ask them to tell you what it says on their thermostat or indoor thermometer
  • Encourage those who may not know they are at higher risk to take cool baths, sleep in the coolest room, or stay with friends
  • If you have air conditioning and higher risk members of your family do not, bring them to your house
  • Never leave children, dependent adults, or pets alone in a parked car, leaving windows open will not help

Learn more: Health Check during Extreme Heat: A Guide to In-Person or Remote Health Checks

  • If you do not have air conditioning, find somewhere with air conditioning especially if you are at increased risk. Spend time in cooler indoor spaces in the community like shopping centres or libraries
  • Sleep in the coolest room of the house, even if that is not your bedroom. Sleeping in the basement or outside will provide relief to the body overnight, if possible. Set that space up for comfort, being sure you have water to drink and easy access to a toilet
  • Open windows and doors when the outdoor temperature goes down below the indoor temperature at night
  • Shut windows and close shutters, curtains, or blinds in the morning to keep cooler air in and to keep the sun out. Leaving windows open during the day lets the hot air indoors
  • Make meals that don't need to be cooked in an oven
  • Protect yourself from the sun by staying in the shade, avoiding direct sun mid-day, wearing a hat and protective clothing, using sunscreen, and wearing UV-protective eyewear.
  • Seek cooler, breezier areas when outdoors, such as large parks with water features and lots of trees.

Important: If you are experiencing extreme heat during an air quality advisory, prioritize cooling down. Heat is typically more dangerous than short-term exposure to poor air quality. 


If you cannot access air conditioning and/or a cool room, consider:

  • wearing a damp shawl or shirt
  • sitting in a cool or tepid bath to draw heat from the body into the water
  • taking a cool shower 
  • using a damp sheet at night
  • putting an ice tray in front of a fan
  • using a personal mister or spray bottle 
Important: While fans can help you feel more comfortable, they do not work to lower body temperature at temperatures over 35C. 
The following tips can help you manage your health during a heat event. 

  • Drink lots of water, even if you do not feel thirsty, especially during warm nights. Pay attention to the amount and colour of your urine. Dark yellow urine is a sign of dangerous dehydration.
  • Lower your activity level and avoid intense activity. It takes time for your body to adapt to heat. If you need to do errands, do them when it is cooler outside, early or late in the day. 
  • Watch out for severe headache, confusion, unsteadiness, loss of thirst, nausea/vomiting -- they are signs of dangerous heat-related illness.
  • If you are experiencing heat-related illness, take immediate action to cool down and call for help if needed. Dangerous heat-related illness is a medical emergency. 
  • Children are not always able to recognize how heat events can affect them. Ensure they stay hydrated with plenty of water. 
  • Apply sunscreen throughout the day; wear hats, sunglasses, and light-weight clothing in breathable materials. 
  • Avoid being outside during the hottest part of the day (approximately 3pm). 
  • Seek shade, air-conditioned spaces such as community centres or libraries, splash pads, waterparks or pools. 

 Pregnant people can be more vulnerable to heat exhaustion or heat stroke than the general public, particularly if they have other health concerns (such as obesity, kidney disease, or heart issues). They have to work harder to cool themselves and their baby down.

  • Lower blood pressure is common, particularly in early pregnancy. Warm conditions bring blood to the skin to get ride of excess heat which can potentially make blood pressure even lower. This can cause headaches, feeling light-headed or even fainting. 
  • Many experience Braxton Hicks contractions in pregnancy and dehydration can make these worse. Hot weather may also cause preterm birth. Anyone who experiences more Braxton Hicks-type uterine activity than usual should be checked by their health-care provider.
  • Drink plenty of water, find ways to stay cool, and avoid increased physical activity during hot weather.

Know the signs of heat-related illness  

Take immediate action to start cooling down if you or the people you care for show signs of heat-related illness. 

Severe heat illness and heat stroke are medical emergencies. Call 9-1-1 if you are caring for someone with signs or symptoms of severe heat-related illness.

  • Severe nausea and vomiting
  • Fainting or loss of consciousness
  • Confusion or disorientation
  • Difficulty speaking
  • Movement and coordination problems
  • Lethargic
  • Not sweating
  • Hot, flushed skin or very pale skin
  • Not urinating or very little urinating
  • Rapid breathing and faint, rapid heart rate
  • Body temperature >39°C (102°F)

While waiting for help to arrive, cool the person by:

  • Moving them to a cool place, if you can;
  • Removing excess clothing.
  • Applying cold water, wet towels or ice packs around the body, especially the neck, armpits, and groin
  • Headache
  • Nausea
  • Weakness
  • Irritability
  • Light-headed or dizziness
  • Disorientation
  • Thirst or dry mouth
  • Difficulty swallowing
  • Fatigue, malaise
  • Heat rash, heat edema or heat cramps
  • Decreased urine output
  • Increased heart rate
  • Skin feels very warm and sweaty
  • Body temperature over 38°C (100°F)

Contact a healthcare provider or call HealthLinkBC at 8-1-1 if you are unsure. Mild to moderate heat illness can quickly become severe. If symptoms get worse, call 9-1-1.

SOURCE: Preparing for Heat Events ( )
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