I can't handle solid food on hot days. Anything more solid than a Shot Blok stands a good chance of becoming pavement decoration, or at least that's how it feels. (I'm okay with almonds provided I eat them a couple at a time, and spread it out, though. Weird.)
If it's a long ride, ~50 and up, say, I'll stop for real food, but I'll take a long break to digest.