The warmest conditions I ever remember hunting in has been the 70s
That's not the Arizona I know. On Saturday of the most recent Labor Day weekend, the high was 117 in east Yuma, and it started raining hard about 4:00 in the afternoon. Rained for hours with lots of lightning. Sunday morning was standing water everywhere and temp went back to about 112. I once (a few years ago)recorded 180F inside the shell of my truck.
Dove excepted; Arizona hunting primarily kicks of in October and runs into the early part of the next year. June,July and August are the hottest Months of the year and the rest of the Months tend to have very comfortable temperatures for the most part. I was out Quail hunting in Southern Arizona a few weeks ago and the early Morning temperature was below freezing. While this is a generalization it obviates the need to hunt in 100+ temperatures.
If you want to go Coyote hunting in July on the low desert you can expect conditions as you describe. Yuma tends to also have some of the highest daytime temperatures on average here. You need to understand that this location for a territorial prison wasn't chosen lightly.

You also have to keep in mind the Arizona has 7 distinct climate zones;the most of any State. This varys from low desert scrub brush to densly forested Ponderosa Pine stands in the Northern part of the State. If I dropped the average person who didn't know the State off in Northern Arizona they'd probably swear they were in Colorado.
Jim