OK... I've got to say something here guys...

Several of you have advised the OP to "Just suck it up and ride"... as if the heat isn't really a factor that you need to worry about... and if you'll read the OP's first post you'll see that advising someone to do that under the conditions that he describes is irresponsible to the point of recklessness.

The fact is that heat coupled with humidity at the levels described by the OP can be very dangerous. The human body has a much more difficult time dealing with those conditions because our biological mechanisms get less and less efficient as the heat and humidity rise. And trust me... it doesn't get much more humid than coastal South Carolina in the summer.

This heat can be dealt with... I ride in it every day... but people's bodies are different. Everyone has different tolerances to heat. Some people act as if a 110F heat index is nothing... but if you aren't aware of what to watch for, a 30 or 40 minute commute is PLENTY of time to get into the danger zone.

I hope the OP will not listen to the bravado of the folks who say "Just ride on, you big sissy"... and listen to those who advise him to proceed... but proceed with caution and preparation. I don't stop riding during the brutal Georgia summers, but I do hydrate... get enough rest... and slow down when my body demands it.

To the OP: Use your head... know your limits... be prepared... and you'll be fine.