In Las Vegas, I see umbrellas on clear sunny days, more than on rainy days. Nobody is scared of the rain, but the sun freaks some people out.
We call them sunfreaks.
No we don't.
At the time of this photo today, the temperature was probably 105 and the sky was clear. This is Las Vegas Boulevard, across from the Sahara hotel; (note the Sahara roller coaster track, and NASCAR cafe sign). Beautiful sunny day.
Humidity is almost nonexistent, but you will feel the heat and be blinded by the sun.
Two serious recommendations:
2-Contact lens rewetting drops
(and water too of course)
If you wear contacts, you may find that you need rewetting drops more often than elsewhere, during the hot months in Las Vegas.
Nights are beautiful.