Lightning often strikes outside of heavy rain and may occur as far as 10 miles away from rainfall. Rubber soles of shoes and tires on a car will protect you from being struck by lightning. These items provide NO protection from lightning. However, you are much safer inside a vehicle than outside. The steel frame of a hard topped vehicle provides increased protection if you are not touching metal.
Thunderstorms produce other hazards as well.
The number 1 thunderstorm killer is flash flooding. Fortunately, the Keys do not experience major problems with freshwater flooding due to the lack of rivers, creeks etc. Another hazard from thunderstorms is large hail. Large hail is generally 1 inch in diameter or larger and can cause a great deal of damage. Large hailstones can fall at speeds faster than 100 mph.