I Live in Florida and ride a lot now. I have a set of tan chaps for summer and a set of black chaps for winter. My Leather jacket is tan with a removable liner, and I'm going to revise the sleeve linings to come out too for the summer! Right now the jacket is just too hot for daytime driving so I wear a cotton jacket - not the best I know in case of a spill, but that's better than heat stroke!
I am making a huge assumption that the vendors selling leahters in Fl offer lighter weight leather to allow for the high heat.
My tan ones are made by "Hot leathers" a company with mid grade quality manufacturing. I've already had to get some of the stitiching repaired, but the leather is comfortable enough.
My black chaps are made by "USA VANCE Leathers" and have a specialized air cooling liners which would probably ctually be cooler than the regularly lined tan chaps, except for the fact that black absorbs sunlight!
Try an alternative color to black for cooler protection. Actually once you've ridden regularly with chaps you hardly notice they are on. - Until you sit on a wet seat!