Will I be cold?
Will I be cold in Las Vegas in September?
Verdict
No — No, comfortable.
Lows stay near 71°F — you won't be reaching for the puffer.
Day vs. night
Day
95°F
Sweltering
Plan indoor hours around the peak of the day.
Night
71°F
Comfortable
Comfortable outside without an extra layer.
Why
Las Vegas in September averages highs of 95°F, lows of 71°F, 2 rainy days.
You can pack for the daytime temps and not worry about the evening dip.