I mean Maricopa county in Arizona when I last lived there was a regular 125-126 degrees during the hottest two weeks of the year. Never drops down below 100 at night. The wind slams you like a blow dryer in the face.
Which means you can still cool off through sweat evaporation. Now when humidity is high, there's already so much water in the air that that doesn't happen. Your sweat doesn't evaporate, so you don't cool down at all. That's deadly.