Couples getting married on July 24, 2021 in Ontario

Is your ceremony exposed or under the cover? I think that'll be the toughest if it's exposed. One thing to keep in mind is, if you're near a large body of water like a lake, it won't be too bad due to the breeze. The sun will be at it's peak but since you have a covering and a water station, it'll be much more bearable than you think.

You could also encourage a much more relaxed dress code. Allow men to wear short sleeve shirts and dress shorts instead of traditional wedding attire where people layer up or wear long sleeves/pants.

Travel size sunscreen bottles would be great wedding favours.

Congratulations!!!!!!!!!!
I think some things you could do would be:
A) Have a water station setup with ice cold water
B) Have hand fans that people can gra to help cool themselves
C) If you can have cold wet towels it will be nice to put a cold compress on your neck or just to swipe your face when its that hot out.

These are just some of the thing we originally had setup for our wedding this year. I think having a tent where there is a shaded area would be a very good idea!