The heat wave in our area has kept us hiding in the air conditioning for several days now. Baxter seems to be the only one who wants to be outside...probably to keep tabs on the neighbor cat. Kirby always seems excited to go out, then hits the hot air and changes his mind. Attempts at dog walks end up with Kirby getting about a block from home, then making a 180 to pull toward home.
Bax has a pretty high heat tolerance -- he's off the ground enough to catch the occasional breeze under his belly. But Kirby, being dark and rather close to the ground, overheats almost immediately.
What's Baxter's secret for beating the heat? A very large tongue. When I'm out with him in the heat (because trips outside must happen, heat wave or not), and he's walking along beside me with his tongue dangling out the side of his mouth, I'm always amazed at just how long and wide that tongue is. A veterinarian friend of mine told me Bax has the biggest tongue she's ever seen. Evaporative cooling.