I was crossing the James River Bridge on my way to work one day when I saw a tornado move from the land onto the river, creating a large and very scary looking waterspout. It was powerful enough to make my car bounce around and scare the crap out of me. I couldn't see anything but horizontal rain and grey outside the windshield. It passed after only several seconds, but, I'll never for get it.
I was sure I was about to get sucked up and dumped into the James.
http://en.wikipedia.org/wiki/James_River_Bridge
Dave