Known as the "underrated killer", Lightning ranks #4 on our list with 60-90 deaths and 500 injuries each year - more than Tornadoes and Hurricanes combined. There is a lot of confusion regarding when and where lightning can strike. The critical rule is this: if thunder can be heard, you are at risk of being struck. The majority of lightning fatalities occur when people resume outdoor activities too soon after a storm has passed. Assuming it is safe to go outside because the rain stopped is flawed reasoning. Consider that lightning can strike ten miles from the base of a thunderstorm. To avoid tragedy, you should wait at least 30 minutes after a storm has passed before going back outside.