Environment Canada has issued a heat warning for the Montreal area, including Châteauguay, La Prairie, Laval, Longueuil and Varennes.
Daytime highs near 30 degrees are expected Sunday and Monday, with humidex values nearing 40.
The weather agency is reminding residents to stay hydrated by drinking plenty of water — even before feeling thirsty — to stay in a cool place and reduce physical activities.
The city of Montreal has announced that some of its outdoor aquatic facilities, including splash parks, will have extended opening hours.
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Call 311 or log on to the City of Montreal website for more information and to check schedules.