Yeah I'm having whole issues with heat index, since my son makes us walk to school. That's 3 miles a day total (for me) in like 100+ heat index temps, and I'm just sure one of these days I'm just gonna drop! UGH! That humidty is a killer for me and I figure it's gotta work similar to the snakes. Healthy animals probably not affected much, but those that arent' might (?) have a higher chance? I don't know I'm just babbling. I'm still recovering from this first week of school!