Extreme heat already causes measurable health impacts in our region and will become more of an issue as the climate warms. These events can trigger a number of heat-related illnesses (such as heat exhaustion, heat stroke) and in extreme situations, can lead to permanent disability or death. Older adults, people with chronic conditions, people on certain medications, infants and young children are especially sensitive to the health effects of heat.
Visit our Heat resources page for more information on staying safe and cool in the heat.
To provide the public and partner organizations with a warning of the health risk from heat events, temperature thresholds have been established by the BC Center for Disease Control in collaboration with Environment and Climate Change Canada, Health Canada, and BC health authorities.
Watch for these heat notifications issued in Vancouver Coastal Health (VCH):
Environment and Climate Change Canada issues a Heat Warning when:
Southwest: (Includes the North Shore, Vancouver, Richmond, Howe Sound, Whistler, Pemberton and the Sunshine Coast as well as Eastern Metro Vancouver including Coquitlam, Surrey, and the Fraser Valley):
Coastal station (Vancouver Airport): Two or more consecutive days of daytime maximum temperatures are expected to reach 29°C or warmer and nighttime minimum temperatures are expected to be at 16°C or warmer.
Inland station (Abbotsford Airport): Two or more consecutive days of daytime maximum temperatures are expected to reach 33°C or warmer and nighttime minimum temperatures are expected to be at 17°C or warmer.
Warnings are issued for both Coastal and Inland sections if either criteria are met.
Northwest (Central and Northern Coast (inland and coastal regions), Northern Vancouver Island, and northwestern BC): Two or more consecutive days of daytime maximum temperatures are expected to reach 28°C or warmer and nighttime minimum temperatures are expected to be at 13°C or warmer.
According to historical BCCDC data, the Heat Warning criteria indicate temperatures at which an increase in deaths in the community is expected.
Note that different temperature thresholds are set for different parts of the province, as the relationship between heat and mortality differs. More information on heat alert criteria for other regions, including a map, can be found here.
For the Southwest region (defined above), VCH and Fraser Health Authority will on occasion issue a joint Extreme Heat Alert when the expected risk to the public is extremely high. This is based on current and forecasted temperature criteria* recommended by the BCCDC in addition to a health authority assessment of anticipated risk to health.
The Extreme Heat Alert criteria indicate temperatures at which a larger increase in deaths in the community is expected. During the 2009 extreme hot weather event there was a 40% increase in regional mortality over a 1-week period.
The Extreme Heat Alert triggers additional responses from the health authority, local government and partner organizations as well as public messaging to strongly encourage individuals and communities to be aware of the risk and take action to stay cool.
*Calculated when the two-day average of high temperatures is predicted to reach 36°C or higher at the Abbotsford Airport and/or is predicted to reach 31°C or higher at the Vancouver airport, based on the temperatures measured at 2pm.
Symptoms of heat illness can range from mild to severe.