score:3
I am visiting Las Vegas as well this August.
What I can tell you from experience: dress in layers have a t-shirt as well as shorts with you, but at the same time take a hoodie or light jacket that you can put on when you enter an establishment.
Like you said, Americans like their AC on max so if you just enter in shirt and shorts after being outside at 40 degrees you are likely to get a cold.
Truth be told I got a light cold nearly every time I visited the US in summer but it went away after a few days every time.
Oh and don't forget to pack something nice for the evening if you plan to go into clubs, most of them have a dress code.
Upvote:1
This is quite based on personal opinion or habit.
Some people are not disturbed at all by the polar AC present inside the buildings. I am! In my 2 visits to Las Vegas I always brought with me a light sweater, which I put on when I was inside, and removed the few times I went outside. During the day the temperature jump from outside to inside is too high for me.