Severe Thunderstorm Awareness Day

There are approximately two thousand thunderstorms in progress around the world at any given time.  Most of these storms are beneficial and bring needed rain.  Only a small fraction less than one percent are classified as severe.  Severe thunderstorms are those thunderstorms that produce hail one inch in diameter or larger and strong wind gusts of 58 mph or greater.  Hail that is one inch in diameter is about the size of a quarter.  A small fraction of these thunderstorms produce tornadoes.  All thunderstorms are capable of producing deadly lightning.  The heavy rains or the lightning activity in a thunderstorm do not have anything to do with a thunderstorm being classified as severe.  Some of the severe thunderstorms safety rules are as follows:

  •  Find shelter immediately.  Go to a sturdy building that will withstand high winds.  Avoid electrical appliances and telephones.
  • It would be a good idea to bring your car inside a garage and to secure loose objects.

Remember, a Severe Thunderstorm Warning means that a severe thunderstorm is occurring.  The severe thunderstorm has been detected by doppler radar, or reported to the National Weather Service by our Skywarn Spotter Network, or the local law enforcement agency in a particular county.

A Severe Thunderstorm Watch means that conditions are right for severe thunderstorms to develop, but none has been observed. People should keep an eye on the sky and listen to commercial broadcasts, or NOAA Weather Radio for any subsequent warnings.

When a severe thunderstorm warning is issued for your location, treat it the same as you would a Tornado Warning.  Severe Thunderstorms can produce damaging winds, large hail, and deadly lightning.

Back to Severe Weather Awareness Week page


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