When the summer temperatures begin to climb cats experience dangerous heat strokes much more easily than humans.
Cats cool themselves by rapid breathing and by licking their coats.
This is why they groom more in warmer weather. As the saliva evaporates from their fur it cools them in a fashion similar to sweat evaporating off of our skin. But once the air temperature is close to, or exceeds, body temperature then the cooling by licking method begins to fail and cats are left with only their tongue 's rapid breathing as a cooling mechanism. As you can imagine this is not sufficient and the possibility of cat heat stroke rises with increasing temperatures. Persians and other short nosed breeds are especially susceptible to heat stroke.