Thought of Poltergeist immediately and so did this guy who says he has a better method (30 X 30) on counting distance. Not sure if it's accurate? (Saw Poltergeist in the theater, 1982, Village Mall, Horsham )
This thing is the gift that keeps on giving. Couple times slowed down a bit only to pick right back up. Lightning and thunder are gone but the rain hasn't left. Thankfully the imaginary drought is over and my car is now free from the dusting of pollen...