Nah, we went 4 months this past summer with no rain. And when it does rain, it's the Virga rain that doesn't even get your jacket wet. It's weird to ride in the rain and never get wet.
The higher portions of Colorado can get some thunderstorms, but the are usually only 1-2 big clouds that move by pretty quickly. Sit down, take a break and watch it pass.
Waiting on a traffic accident to be cleared before the road opens - in rain as hard as it gets in the desert. Jacket isn't even wet....