Heat might be the enemy of pie dough, but that doesn't mean you should stop (or can resist) baking pie on the hottest days of the year, in your tiny kitchen, without A/C or even a fan, wearing only your bathing suit. (Come on, I know I'm not the only one.)
It's not only the air temperature that's disturbing your dough. When the temp in your kitchen rises above 73° F (for me, that's all summer long), Parks says "that everything from your countertop to your rolling pin and the flour itself will act as a heat source to the butter." To protect your butter, refrigerate pie plates, rolling pins, and dry ingredients until cool (but not cold or frozen).
And, if it's really steamy, buy a few bags of ice from the convenience store: Wrap them in kitchen towels (to absorb moisture), then spread them over your counter. The ice water should chill down your surface, making it less likely that your dough will melt into a sticky, uncooperative glom.
So go forth and make pie: A little heat can't stop you!
A (former) student of English, a lover of raisins, a user of comma splices. My spirit animal is an eggplant. I'm probably the person who picked all of the cookie dough out of the cookie dough ice cream. For that, I'm sorry.