The typical thunderstorm is 15 miles in diameter and lasts an average of thirty minutes. Florida has more thunderstorms and lightning strikes each year than anywhere else in the United States. Florida also leads the nation in deaths and injuries from lightning, averaging 10 deaths and 30 injuries each year. Although all thunderstorms are dangerous, produce lightning, and can be lethal, about 10% produce dangerous winds or hail that will likely exceed thresholds known to cause bodily harm or significant damage to well-built structures. These are known as severe thunderstorms.