In the United States, there are an estimated 25 million lightning flashes each year. During the past 30 years, lightning killed an average of 66 people per year. This is more than the average of deaths per year caused by tornadoes. Yet because lightning usually claims only one or two victims at a time and does not cause mass destruction of property, it is underrated as a risk. While documented lightning injuries in the United States average about 300 per year, undocumented injuries likely much higher.
Watch for Developing Thunderstorms:
Thunderstorms are most likely to develop on spring or summer days but can occur year round. As the sun heats the air, pockets of warmer air start to rise and cumulus clouds form. Continued heating can cause these clouds to grow vertically into towering cumulus clouds, often the first sign of a developing thunderstorm.
An Approaching Thunderstorm:
Lightning can strike as far as 10 miles from area where it is raining. That's about the distance you can hear thunder. If you can hear thunder, you are within striking distance. Seek safe shelter immediately.
If you can see lightning or hear thunder you are already at risk! Most lightning injuries and fatalities occur when people are caught outdoors in the summer months during the afternoon and evening.
Most lightning deaths and injuries occur in the summer.
If you are outdoors when you see or hear a thunderstorm coming or your hair stands on end, immediately stop your activities and seek safe shelter immediately!
The first 30 means if, between flash and bang, you count to 30 or less, you are in danger and should go to safe shelter.
Flash-to-bang: When you see the FLASH, Count the seconds to the BANG, Every 5 seconds equals 1 mile. Divide by 5 to give the distance in miles from you to the lightning.
30 seconds - suspend all outdoor activities (lightning strike was 6 miles away or less) and seek safe shelter
If you count 15 seconds or less, a lightning strike could occur where you are (3 miles away or less).
The second 30 means wait 30 minutes from the last flash or thunder to establish "all clear.
No place is completely safe from lightning, but some places are safer than others. Although some victims are struck directly by the main lightning stroke, many victims are struck as the current moves in and along the ground.
Helping a Lightning Strike Victim:
For this and more information visit www.lightningsafety.noaa.gov/