'Heat event' bringing temperatures up to 40 C about to hit GTA

The Greater Toronto Area is about to be hit with a major “heat event,” with temperatures soaring to about 40 C with humidex.

In a weather statement, Environment Canada said the temperature change is expected to start on Sunday and last between three to five days.

“A hot airmass is expected to affect the area beginning Sunday and persisting into Wednesday,” the alert says.

“Despite overnight temperatures being lower than warning criteria in some areas, humidex and daytime highs will be very atypical of early September.”

The weather agency warned that high humidity can bring deteriorating air quality. Temperatures are expected to reach a high of about 30 C, or between 35 C and 40 C with humidity.

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Environment Canada is warning residents to stay hydrated and check on vulnerable family members and friends.

The sudden heat wave will likely be a shock for a city that hasn’t seen temperatures rise above 30 C throughout the month of August.

“Normally, we’d see about four or five of those days in August – we got none,” ECCC Senior Climatologist David Phillips told CTV News Toronto Thursday."It's definitely been on the coolish and wetish side -- almost half the days this summer have been wet."

Phillips said that throughout the summer Toronto has only seen temperatures of over 30 C eight times.