Just summertime heat???

I haven't been around here in a LONG time because school has been insanely busy, but need advice from the experts! Chloe seems very lazy and needy the last couple of days. She has occassional spurts of her usual craziness where she hurdles a chair or plays with her stuffed animals, but is laying around a lot and always seems to want to be held. When I say held, I mean like a baby, almost completely curled up, where I can carry her in one arm. I'm wondering if the hot temperatures that have hit (90+) this week are just getting to her - I know they're getting to me! I'm making sure she's got extra water on hand, and try to keep a window open so she can get a breeze.
What do you think?

Cats do become less active when the temperature rises -- the hotter it is, the lazier the cat! But...please keep an eye on her eating, drinking, potty habits and grooming. If all of these seem okay, I would not be too concerned. However, if you find a change in one of these areas, a vet visit might be a good idea.