I live in an area where it is regularly 95°F+ (35°C). Yesterday was ~105°F (just over 40°C), and about 75% humidity for my 1.5 hrs on the road. I'd love to have a mid-day ride at 33°C... down right temperate. If you can get out in the morning, like others have said, then that's the best option.
Anyway, I want to echo to drink a lot of water, and not just during the ride. Drink a lot a regular intervals before your planned ride, and after. Do not drink cold water on the bike either, just cool water. I'll start a ride with 2 water bottles, one filled with tap water, and the other with ice and water. By the time I finish drinking the first bottle (and the water is pretty warm by then), the next bottle is a little colder than cool.
The solar sleeves idea is great. I actually use arm and leg coolers (same idea, and I use the Sugoi brand). The white color keeps a lot of the radiant heat off my skin, and the wicking fabric helps facilitate evaporative cooling.
Lastly, read up on the signs of heat exhaustion. If you start to experience those, then stop in some shade, drink water and recover. Other than that, your body will only allow you to push so hard.