There are allot of variables there. Depending on how hard the rain is and how fast you're driving you could stay fairly dry or you could get soaked. If I am running that way, I try to keep driving and hardly get wet. Then again, there was a time a couple of years ago when a freak storm came in and swamped my Jeep in the parking lot at work.
Now adays I have water proof seat covers, removed the carpeting and bed lined the tub.