Mesh jackets are the way to go for hot weather riding.
I wear one every time I get on the bike in the summertime here.
That's 117 degree heat.
It actually keeps me a little cooler as I don't have the sun directly on my skin. It's kind of like riding in the shade
And the full face helmet negates the "blast furnace" effect of 117 degree air at 80 mph.
