There's a point where you're better off being covered than letting air in. On long rides I always ride with long sleeve LDcomfort top, and the full leg tights under a full Aerostich Roadcrafter 1pc suit. I've never had any problem even at 108 degrees. Mostly dry around here, but I've ridden in MO, Arkansas, eastern Kansas and Nebraska, Iowa, Texas, Oklahoma and so on. I'm sure some of it must have been humid. I never can tell the difference. All I care is the temperature. The GL1800 is good in heat. I enjoy heat, one of the few I suppose. Also I never use AC as I don't have it at work or at home, got it in my truck, but could care less. I never use it. I think being used to hot helps.