Waterbizkit
Explorer
As I posted above, there are already rules for this in the DMG. If it's at or above 100 degrees F, then you make your save every hour if you don't have ample water.
Oh yeah, I get that. I saw your earlier post. What I meant was whether or not the AP will give us an idea of just how hot it actually is in a Chultan jungle. For example, even with a whopping 90% relative humidity the air temperature needs to be 85 degrees before the heat index breaks 100 degrees. Some cursory research seems to indicate that it actually rarely breaks 100 degrees in the jungle, even when factoring in the humidity. Average annual temps seem to be in the 80's with humidity between 77-88%.
So like I said, I'm curious what the book will say, if it gives any guidelines at all. Will the AP leave it to the DM to say it might be over 100 degrees? Will the book just say "Hey man, it's really hot in the jungle. If you wear medium or heavy armor get ready to make some con saves!" Paraphrasing of course. Or maybe it says nothing and it's up to the DM to figure it all out.