I commuted almost 500 miles in July, going home between 4 and 5:30pm most days. Pretty sure it was upper 90's to 100 a few times. Gotta say I love it. I fill up a 24 oz bottle of ice water and mix in some orange creme zip fizz. Then after 18 or 19 miles I stop under a bridge by a creek and drink it, still ice cold from being in my pannier. Just about the best part of the day
Love the hot sun this time of year, especially since I leave the house at 6am which is now sunrise and I see the days are getting shorter again.