Currently 98/112 out. Not really pleasant out.
I remember being in Vegas a few years ago and finally learning what a 'dry heat' was. It was 105-110 during the days and I rarely worked up a sweat even when walking from casino to casino. My mom was bitching the whole time about me not drinking enough water because it was so hot out and all I drank was beer. Then I told her I hadn't sweated since we got there and she backed off.
The humidity is one of the worst parts about mid-west living. It can be 79 degrees out, but with high humidity you can't see because the sweat burns your eyes.
I would have been concerned if you told me you weren't sweating. Not sweating doesn't mean you are cool enough to not sweat. Lack of sweat, in high temps, is a sign of dehydration. Even in a dry heat, you sweat a little, certainly not like places with a lot of humidity, but you still sweat.
Unfortunately, I've got some history with dehydration. Sometimes on the golf course, you simply can't hydrate enough. One time I played the first 15 holes of a course sweating profusely and the final 3 holes bone dry. After the round, a doctor friend of mine in the group ahead of us drove me to his office for a round of IVs and a lecture about how stupid it was.
My time in Vegas was not spent on anything physically challenging, nothing more than walking and after living through Indiana summers, I didn't find Vegas to feel hot. Granted, it was only 105ish; but I've heard horror stories of 115-120 out there.