Hi!
Perhaps talk to your T about having reversed seasonal affective disorder? My worst time of year is August through the end of September, which August is the hottest month of the year here. Also, at season shifts things can be harder for some reason.
I also hate the heat. I swell up. My hands and feet especially. It's very uncomfortable.
My coping skills are basically just to bulldoze through anything I'm facing. It's not really the best thing, maybe. But like I force myself to get up and go and take shower, etc. Sometimes it's easier than other times. Maybe if you're feeling overheated take a cold shower. Cold water when you're hot is wonderful.