I was driving north on the highway and talking on my (bluetooth) cell phone talking and I actually instinctively uttered out loud, "Oh my God!" and my reaction was to duck. It was SO VERY bright and was arcing from my right to my left! Then it disappeared. The person on the phone thought something was wrong due to my reaction. I was blown away to have seen this. I've never experienced anything even close. It was pretty awesome!!! I immediately told my friend on the phone that I'd seen my first fireball.
