Severe Thunderstorm

What is a Thunderstorm?

Know the Terms

A Severe Thunderstorm Watchis issued when conditions are favorable for the development of a severe thunderstorm. 

A Severe Thunderstorm Warning is issued when radar or an on-the-ground spotter reports a thunderstorm producing hail of at least 3/4 inch in diameter, and winds exceeding 58 miles per hour. When you hear this warning, you should take cover immediately.

A thunderstorm is a strong storm containing lightning caused by unstable atmospheric conditions.  When cold upper air sinks and warm, moist air rises, storm clouds or “thunderheads” develop.  Thunderstorms may occur by themselves, in clusters, or in lines.  So, it is possible for many thunderstorms to affect one location in the course of a few hours.  Some of the most severe weather occurs when a single thunderstorm affects one location for an extended period of time.

How can I stay safe during a Thunderstorm?

Severe thunderstorms can bring heavy rains, which can cause flash flooding, as well as strong winds, hail, lighting and can even spawn tornadoes. Severe thunderstorms can produce hail up to 3/4 of an inch or larger in diameter, and winds that exceed 58 miles per hour.   To protect yourself during a severe thunderstorm, it is best to get inside a sturdy building and stay tuned to a battery-operated radio for weather information.

You can also monitor a NOAA Weather Radio or your local media for information on when watches and warnings are issued in advance of severe thunderstorms. The National Weather Service will issue watches and warnings depending on the level of threat.

Make sure your family knows what to do when they see thunderstorms forming.  Be sure to stress the importance of finding shelter in a sturdy building and to avoid going outside until the threat passes.  If you can hear thunder, you can be struck by lightning!

Where can I get more information on Thunderstorms?

The National Severe Storms Laboratory has information on the science of thunderstorms, how they form, and the dangers associated with different types of thunderstorms.

NOAA Weather Radios are one of the best ways to make sure you receive severe thunderstorm watch and warning information. You can purchase these from various vendors across the Houston area, from the American Red Cross Store, and online electronics retailers.