Thunderstorm Safety


The damage you see in the image above took place at a shopping center in Kingsport, TN on September 3, 2011. The back wall of a Hobby Lobby store collapsed with shoppers still inside. A natural gas line ruptured. A canopy blew off another store and crashed into the lobby of a nearby Fazoli’s. Trees were downed and traffic lights ripped from their poles. Luckily, there were no serious injuries.

Many thought this had to be the result of a tornado. But, there was no tornado. The damage occurred due to straight-line winds produced by a severe thunderstorm. In fact, this damage took place before the NWS even issued a Severe Thunderstorm Warning.

Thunderstorms, whether severe or not, are dangerous. They produce several hazards that cause injury or death, such as lightning, strong winds, and flash flooding. All thunderstorms pose a risk to life and property. Remember, when thunder roars, go indoors!


What is a Thunderstorm?

A thunderstorm is a storm with lightning and thunder.


What is a Severe Thunderstorm?

A thunderstorm is considered to be “severe” when it is capable of producing:

  • hail over 1 inch in diameter
  • winds in excess of 58 mph
  • a tornado




Hail can not only cause property damage, but can also result in serious injury and even death. Large hail can easily shatter windows and windshields.


Straight-line winds over 58 mph are capable of toppling small trees and causing damage to structures. Tall vehicles are susceptible to rolling over.

Downbursts may also cause significant damage. Downburst damage can be so extensive they are often confused with tornadoes.

Heavy Rain

Heavy rain accompanies nearly every strong to severe thunderstorm. Flash flooding may occur, so avoid low-lying areas prone to flooding such as creeks, gullies, and ditches. NEVER drive through flooded roadways.


If you can hear thunder, you are close enough to be struck by lightning. Do not resume outdoor activities until 30 minutes has passed since the last rumble of thunder.


Watch vs Warning

Issued by the Storm Prediction Center in Norman, OK when conditions are favorable for the development of severe thunderstorms within the next 3-6 hours.

  • Remain alert to changing weather conditions
  • Monitor NOAA Weather Radio or local media for updates and warnings
  • Be prepared to seek shelter ASAP in the event a warning is issued
SEVERE THUNDERSTORM WARNING Issued by the local National Weather Service office (ours is in Morristown) when a thunderstorm is capable of producing hail over one inch in diameter or winds in excess of 58 mph.Seek Shelter Immediately!

  • Seek shelter in a sturdy building capable of protecting you from damaging wind, large hail, lightning, and flash flooding.
  • Stay away from windows, electrical equipment, and plumbing.
  • If a study building is not close, seek shelter in a hard top automobile. Role up the windows and do not touch any metal or electronics.
  • If caught outdoors, avoid open spaces, water, and tall objects such as trees and power poles. DO NOT seek shelter under a tree.
  • If on the water, come to sure immediately and seek shelter.


Safety Tips

  • DO seek adequate shelter when a Severe Thunderstorm Warning or Tornado Warning is issued.
  • DO be alert to flash flooding and rising water as a result of a thunderstorm.
  • DO monitor NOAA Weather Radio and local media for the latest weather updates.
  • DO be prepared by having a severe weather plan and an emergency supplies kit.
  • DO NOT seek shelter under tall objects, such as trees, telephone poles, and metal towers.
  • DO NOT seek shelter under highway overpasses.
  • NEVER drive through a flooded roadway. It only takes a few inches of water to float a vehicle.


More Info

Tornado Safety

Lightning Safety

Weather Safety 101