High heat and humidity will return for Tuesday.
Environment Canada said the airmass would settle over Nova Scotia, New Brunswick, and P.E.I. over the weekend, bringing humidex values exceeding 36 C.
Overnight low temperatures are forecast in the mid-teens, providing some relief from the heat of the weekend.
Environment Canada says temperatures could reach the mid-30s with humidex values into the mid-40s, while overnight lows are expected to be in the mid 20s, providing little or no relief from the heat.
A heat wave is usually announced, when the air warms up above 32 With three days in a row. "Daytime highs again will be near mid-thirties with humidex near mid-forties".
The heat wave was a definitive sign of the arrival of summer in the Maritimes, just weeks after frost caused widespread damage to crops throughout the region.
The move is part of the federal government's climate change adaptation in expectation of more frequent heat events.
Limit or avoid direct exposure to the sun and wear a sunscreen with SPF 30 or higher, a wide-brimmed hat, sunglasses and SPF lip balm.
Look for shade or a cool shelter in an air-conditioned location such as a shopping mall, local library or community centre. However, if working outside, make sure to take frequent breaks in cool areas. Focus on cooling the back of the neck, under the arms and groin area.
Stay connected with people in your community who have a hard time coping with hot weather and those who live alone and check on them regularly.