Summerside and all of Prince Edward Island are under a Yellow Heat Warning from Environment Canada through Friday, with daytime temperatures near 30 degrees Celsius and Humidex values reaching 36 to 38.
As of 5:00 PM ADT on Wednesday, the temperature in Summerside was 29.5 degrees Celsius with a Humidex of 37, according to Environment Canada observations. The hot weather is expected to continue Thursday and Friday, with daytime highs of 30 and 29 degrees Celsius, respectively.
Nighttime lows will stay warm at 19 to 20 degrees Celsius, providing little relief from the heat. The warning, which indicates a moderate impact level with high forecast confidence, extends through Friday, with conditions forecast to improve over the weekend as temperatures return to the seasonal norm of about 23 degrees Celsius.
Heat warnings are issued when temperatures are forecast to exceed 28 degrees Celsius for two or more consecutive days with overnight lows not dropping below 18 degrees Celsius. These conditions pose an elevated risk of heat illnesses such as heat stroke and heat exhaustion. Signs of heat exhaustion include headache, nausea, dizziness, thirst, dark urine, and intense fatigue. Heat stroke is a medical emergency with symptoms including red and hot skin, confusion, and changes in consciousness.
Summerside has a significant senior population, with about 24 per cent of residents aged 65 and over. The community is particularly vulnerable during extreme heat. Residents are advised to stay hydrated, check on vulnerable neighbours, and limit outdoor activities during peak afternoon heat.
Prince Edward Island is developing a province-wide Heat Alert and Response System after being one of the last provinces without such a framework. The province experienced three heat waves in 2024 and has seen increasing frequency of extreme heat events.
