"Not in New Mexico I wager"

You got that right! Where I fly the airfield is 128 ft. ASL, we spend a lot of time at or below ridge heights of 4000-6000 feet ASL and to go above 12,500 you need permission from ATC - which is seldom granted. The cockpit is usually a comfortable shirtsleeve temperature - except during the summer on a day with weak lift where you end up sweating buckets as you scratch away at low speed below 3000 for the whole flight.