Environment Canada has issued a Heat Warning for much of southern Ontario with “extreme heat” expected throughout the region today and tomorrow.
The weather agency says temperatures will be in the low 30s ,with humidex values reaching the mid-to-high 30s.
It says Tropical depression Cristobal will approach Ontario tomorrow night, causing temperatures to cool off.
The normal high for this time of year is 23C.
Will any records be broken? It depends where you live.
In Orillia, the highest temperature on file is 28.5C on this day in 2005. Tomorrow, 29.7C also set in 2005.
In Collingwood, the highest temperature on file is 31.8C on this day in 2005, 31.7C for tomorrow (set in 2000).
In Muskoka, the highest temperature on file is 31.0C on this day in 2005. Tomorrow, the record high is 31.1C set in 2012.
For more details on the Heat Warning, please click here.



