it seriously cannot be so hot in Memphis, that halfway around the world in 120 degree days, desert nomads covers themselves in layers of black cloth and soldiers romp around in 20lbs of uniform and protective gear.
None of them are dying of heatstroke. Drink water!
Long pants don't make you hotter, heat doesn't build up in the body from your ankles to your knees. IF anything if you a riding a mower, it's better to have your legs covered to protect from sunburn than have them uncovered. Short pants are a psychological advantage. nothing more.
Unless you are going to get wet a lot (like working with water features or irrigation) there is no actual benefit from shorts.
wet long pants tend to sag and hang and weigh more than shorts… other than that.. long pants protect better.
Besides who wants green hairy legs from the weed whacker?