Hottest Day of the Year So Far. Long Run. What could go wrong?

Clearly, I overestimated my ability to run in the heat. I took 2X 20 0z. water bottles and off I headed to the ravine.Beaver had invited me out for a 6:30 am run, but I was unable to go that early because of work.

    I slept 'till noon and didn't leave the house until 1:00p.m. It was kind of like running in a bowl of soup outside, just over 100˚F and feeling like 122˚F (37˚C feeling like 50˚C) with the humidity.
  So out I headed at what was probably the peak daytime temperature.I think you can see where this is headed.
 After 40 minutes of fairly decent running, I felt like my shirt was really heating up. Weird. It was soaked with sweat, and I guess the sun heated it higher than my body temperature. I felt my arm and it felt hot to me. 10 minutes later, I got that familiar dizzy feeling which tells me I better stop or I'm going down. I started walking, then recovered enough to do a slow run/walk back home. All in all, 1:40 on my feet and some decent heat training as well. I'll try an hour today, and then do a long run on Sunday when it's s'posed to be a bit cooler with a chance of rain.