I wouldn't ride in a bra either. Ba-doomp-BISH
Okay, sophomoric joke out of the way.
I do golf course maintenance, so I'm either on a tractor or on the ground working with hand tools 6-10 hours a day. Either way I'm outdoors all day. By comparison my bike commutes to work before daylight in the morning and going home in the middle of the afternoon are quite pleasant. Stay well hydrated and start drinking water before you need it. I am quite comfortable on the bike even then the mercury is pushing triple digits, but I soon as I stop my t-shirt is soaked with sweat in a matter of minutes. One thing I do that I think helps is we almost never run the air-conditioning in the house.