Thunderstorms affect relatively small areas when compared with hurricanes and winter storms. Despite their small size, all thunderstorms are dangerous because they can produce strong winds, lightning, tornadoes, hail and flash flooding. The typical thunderstorm is 15 miles in diameter and lasts an average of 30 minutes.
Last year, at least 500 thunderstorms occurred in Georgia on about 80 separate days but only about 10 percent of these thunderstorms were severe. The biggest threat in Georgia from severe thunderstorms is damaging straight line winds and large hail, according to the Georgia Emergency Management Agency.
Straight line winds can reach speeds in excess of 100 m.p.h. and produce damage similar to a tornado. These winds occur, on average, 19 days per year in Georgia. These events have occurred in every month of the year, but are most common in the spring and summer months, peaking in July.
To prepare for a thunderstorm:
- Remove dead or rotting trees and branches that could fall and cause injury or damage during a severe thunderstorm.
- Remember the 30/30 lightning safety rule: Go indoors if, after seeing lightning, you cannot count to 30 before hearing thunder. Stay indoors for 30 minutes after hearing the last clap of thunder.
If a thunderstorm is likely in your area:
- Postpone outdoor activities.
- Get inside a home, building, or hard top automobile. Although you may be injured if lightning strikes your car, you are much safer inside a vehicle than outside.
- Remember, rubber-soled shoes and rubber tires provide no protection from lightning. However, the steel frame of a hard-topped vehicle provides increased protection if you are not touching metal.
- Secure outdoor objects that could blow away or cause damage.
- Shutter windows and secure outside doors. If shutters are not available, close window blinds, shades, or curtains.
- Avoid showering or bathing. Plumbing and bathroom fixtures can conduct electricity.
- Use a corded telephone only for emergencies. Cordless and cellular telephones are safe to use.
- Unplug appliances and other electrical items such as computers and turn off air conditioners.
- Use your battery-operated NOAA Weather Radio for updates from local officials.