It was 101°F here the other day and rode out to give a buddy with some stuff. Long pants, full face noggin protector and an armored jacket. I hardly ever wear gloves, but should get in to the habit.
Admittedly, that ride would have sucked if I planning on a lot of stop and go traffic, but there's not much of that in my area.
Seriously consider a ventilated or mesh jacket. The jacket will shade you from the sun while still allowing full airflow, provided you get a good quality jacket.
I get lots of looks, and sometimes a few remarks, when I'm walking around in my jacket, but they just won't believe it's cooler with it than without.
I highly recommend the Baron mesh from River Road. I normally wear a 1X K large, but since I don't plan to use this jacket with its removable liner ( I have a non-mesh jacket for cold weather) I bought one size smaller. Nice and snug as an armored jacket should be.
It was a white t-shirt and jeans for me. I'll be looking into a decent vented jacket soon. Yeah the ride was fine just didn't think about the sun in the afternoon. Oh well, I'll stick to morning rides on the weekends till it cools off a bit here in Hel...I mean Phoenix.
Somewhere in Phoenix...Damn its hot
A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed. ~ Second Amendment of the United States