Environment Canada has issued a special weather statement for Waterloo Region and the Guelph area with high daytime temperatures expected for the rest of the work week.
The weather office said a hot and humid air mass has reached the area and will remain in place through Friday.
Maximum afternoon temperatures near 30 C are expected with humidex values in the high 30s.
Some relief will come at night with overnight temperatures dropping to the 17 C to 20 C range.
Environment Canada said a cold front on Friday night will bring cooler temperatures and lower humidity for the weekend.
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