My morning commute is 17 miles. I always check the radar before I leave. I figure if its not raining when I leave and I feel like I can beat the rain if there is some on the map then I'll ride. If it rains on my way home, eh whatever. Either way I'm going to be wet when I get to my destination.

+1 On the fenders. It'll keep all the road grime off of you when it is raining. And rain gear. And Lights.

Someone said to me "There is no bad weather, only bad clothing."

Your first ride in the rain will be amazing.

Good luck!