I've done other rides where I saw 126 degrees and was riding over 15 mph, and it was definitely nowhere near that hot for the "air temps". Air temps are also taken 30 feet above the ground. I don't typically ride 30 feet above the ground. Either way, I've been in Death Valley in the summer where the car was reporting temps close to this (slightly above, actually), and it felt the same......so, yeah. Also, the Australian Open (back when I used to watch tennis) used to routinely clock on-court temps in the 150+ degree range (obviously the "air temps" were nowhere near this)....and they're not riding along at 15+ mph taking temps there. Keep in mind I lived in SoCal for 5 years, and this was the one day where it got this hot....like I said, my previous "record" for that section was well below this at 126 degrees and I would routinely see temps on the Garmin in the 115-120 range on afternoon rides (and riding faster than 15 mph). I just went at the hottest time of the day and knew where the hottest part of that ride was, so aimed to be there around that time. The rest of the ride was much "cooler", around 125-132 degrees. It was hot enough to where riding faster with generating a breeze did nothing to help cool down.

Then there was this ride....was averaging nearly 120 degrees for 90 minutes or so and got up to 126: https://www.strava.com/activities/4022794760/


Me in the middle w/ the HR strap showing