Always remember to exit the pool if lightning is visable. 1125 feet per second is the speed of sound. If you see a flash of lightning start counting. Flash! 1234 and thunder! The strike was just under a mile away. 1125 x 4 = 4500. a mile is 5280 feet. Now count the next strike and see if the storm is coming closer or moving away. Counting the visable flash to thunder sound is an important aspect for all hikers.