Fan and spray bottle of water.
Pets got very hot while evac'ing Rita. Temps were high 90s, maybe even 100s; traffic was very slow or not moving at all, so no wind to cool them, and the truck overheated if running the AC while in park for long periods of time. I sprayed their tummies and used a small towel to apply water to their ears, then fanned them.
I hadn't even thought of that but having been trapped on a freeway for HOURS, it makes a lot of sense.
BTW, when you mention a fan...I assume you mean a folding hand fan or something similar, correct?