tornadoes....from National Severe Storms Laboratory

• Tornado Myths: 

  • Myth:  Areas near rivers, lakes and mountains are safe from tornadoes.

    Fact:  No place is safe from tornadoes. In the late 1980's, a tornado swept through Yellowstone National Park leaving a path of destruction up and down a 10,000 foot mountain.

  • Myth:  The low pressure with a tornado causes buildings to "explode" as the tornado passes overhead.

    Fact:  Violent winds and debris slamming into buildings cause most structural damage.

  • Myth:  Windows should be opened before a tornado approaches to equalize pressure and minimize damage.

    Fact:  Opening windows allows damaging winds to enter the structure. Leave the windows alone; instead, immediately go to a safe place.

• Frequency of Tornadoes: 

  • Tornadoes can occur at any time of the year.

  • In the southern states, peak tornado occurrence is in March through May, while peak months in the northern states are during the summer.

  • Note, in some states, a secondary tornado maximum occurs in the fall.

  • Tornadoes are most likely to occur between 3 and 9 p.m. but have been known to occur at all hours of the day or night.

  • The average tornado moves from southwest to northwest, but tornadoes have been known to move in any direction. The average forward speed is 30 mph but may vary from nearly stationary to 70 mph.

  • The total number of tornadoes is probably higher than indicated in the western states.  Sparse population reduces the number reported.

  • USAToday.com (4-3-06) reports "Tornadoes are commonly associated with the nation's heartland-in a 10-state area stretching from Texas to Nebraska that also include Colorado, Iowa, Illinois, Indiana, Missouri, and Arkansas, known as Tornado Alley.  But they are not limited to this region. Tornadoes have occurred in all 50 states and are, in fact, more common in Florida than they are in Oklahoma. Florida tornadoes are generally weak - for tornadoes - with winds around 100 mph.  Tornadoes that have hit Oklahoma, on the other hand, are some of the most violent on record.  A tornado that struck Oklahoma City and its southern suburbs in 1999 had winds of nearly 320 just above the ground."

• Environmental Clues:

  • Dark, often greenish sky

  • Wall cloud

  • Large Hail

  • Loud roar, similar to a freight train

  • Caution:

    Some tornadoes appear as a visible funnel cloud extending only partially to the ground.  Look for debris below the visible funnel.

    Some tornadoes are clearly visible while others are obscured by rain or nearby low-hanging clouds.

• Stay Informed About The Storm:

  • When conditions are favorable for severe weather to develop, a WATCH is issued.

  • Information from weather radar, spotters, and other sources are used and tornado WARNINGS are issued for areas where severe weather is imminent.

  • WARNINGS are passed to local radio and television stations serving the warned areas.  These warnings are also relayed to local emergency management and public safety officials who can activate local warning systems to alert communities.

• What To Listen For:

  • TORNADO WATCH:  Tornadoes are possible in your area. Remain alert for approaching storms.

  • TORNADO WARNING: A tornado has been sighted or indicated by weather radar.  If a warning is issued for your area, move to your pre-designated place of safety.

  • SEVERE THUNDERSTORM WATCH:  Severe thunderstorms are possible in your area.

  • SEVERE THUNDERSTORM WARNING:  Severe thunderstorms are occurring.

• What YOU can do:

  • Develop a plan with your family, for work, school and when outdoors

  • Have frequent drills

  • Know the county/parish in which you live, and keep a highway map nearby to follow storm movement from weather bulletins

  • Listen to the radio or television for information

  • Have a NOAA Weather Radio with a warning alarm tone and battery back-up to receive warnings

  • If planning a trip outdoors, listen to the latest forecasts and take necessary action if threatening weather is possible

• What to do???

  • In a home or building, move to a pre-designated shelter, such as a basement

  • If an underground shelter is not available, move to an interior room or hallway on the lowest floor and get under a sturdy piece of furniture.

  • Stay away from windows.

  • Get out of automobiles.

  • Don't try to outrun a tornado in your car; instead, leave it immediately.

  • Mobile homes, even if tied down, offer little protection from tornadoes and should be abandoned.

  • Occasionally, tornadoes develop so rapidly that advance warning is not possible.  Remain alert for signs of an approaching tornado.  Flying debris from tornadoes causes most deaths and injuries.

• If You Have A Loss:

  • To Your Home

  • To Your Auto

  • To Your Business

  • To Your Farm

• For More Information On Tornadoes, Check Out These Websites:

  • National Severe Storms Laboratory    http://www.nssl.noaa.gov/

  • National Weather Service                   www.nws.noaa.gov  (search "tornadoes")

  • National Oceanic & Atmospheric Administration   http://www.noaa.gov/tornadoes.html

  • Why Files                                         http://whyfiles.org/013tornado/

   

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