I live in good, old Georgia, and it finally started getting real hot and humid this week. Yesterday, I was working out in the tool shed in 100o + humid weather. I kept my set up (eGo twist / Protank) in the shade, and it behaved just fine. However, I have noticed that nicotine and heat just don't really mix for me. Just too dang hot to have a vape. I noticed this with the analogs in my previous life as a stinkie as well. I've heard of people keeping a little cooler for their gear on the go just to be a little extra cautious, which is not a bad idea because I've also read about juice going bad from being out in the sun too long and making folks sick. Moral of the story here is to keep the gear protected and at the very least in the shade.
Be careful out there, vapers, and vape on, vape on.