117 faranheit in 29 Palms, CA. Pretty damn hot.
North Carolina/Virginia in the summer may have been worse though. Damn humidity.
We had a transformer blow this past Summer and within ten minutes the kitchen was 150F. The general manager insisted that we still serve cold food, so I let everybody else go, padlocked the walk-ins and finished service by my self.Just above 110 F in southern california but I've found that 90+ with high humidity feels worse than that.
Hottest man made environment i ever worked in was an improperly ventilated restaurant kitchen when I was young. One day on 4th of july weekend we left a thermometer out after the lunch rush had died down and it was 131 F. The sick part is it had felt hotter than that about an hour prior in the middle of the rush.
All the guys in the kitchen there would drink 5+ pitchers of ice water EACH just to get through a shift and we would still get heat rashes and need to take breaks for fresh 80 degree air outside.