How Is a Tornado Watch Different From a Tornado Warning?

Baca / Campo tornado
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The difference between a tornado watch and a tornado warning means the difference between taking action or taking precautions. A watch means that conditions are favorable for a tornado to occur, while a warning means that a tornado has been seen or picked up by radar. A warning requires you to take shelter and brace for a potential tornado.

There are two general zones in the U.S. that are common tornado locations: Tornado Alley and Dixie Alley. These two areas include a stretch of midwestern and southern states, from Illinois down to Texas and Arkansas over to North Carolina, respectively, so when you're visiting these areas, especially in spring, be prepared for high winds and weather alerts.

Tornado Watch

A tornado watch is issued to alert people to the possibility of a tornado developing in your area. At this point, a tornado has not been seen, but the conditions are very favorable for tornados to occur at any moment.

Signs that a tornado may be heading your way can include dark greenish or orange-gray skies; large hail; large, dark, low-lying, rotating, or funnel-shaped clouds; or a loud roar that is similar to the sound of a freight train.

What You Need to Do During a Watch

  • Keep alert and watch for changing weather conditions.
  • Listen to your local news reports and weather updates.
  • Review your family or business emergency preparedness plan.
  • Review your disaster kit.
  • Be ready to see shelter at a moment's notice.

Tornado Warning

A tornado warning is issued when a tornado has actually been sighted or has been picked up on the radar in your area. This means that you need to take shelter immediately in a safe, sturdy structure.

illustration of woman and young girl taking shelter inside as a tornado is seen outside the window
TripSavvy / Ashley Nicole DeLeon

The National Weather Service recommends that you go to a pre-designated shelter such as a safe room, basement, storm cellar, or the building's lowest level. If you don't have a basement, take shelter in the center of an interior room on the lowest level, such as a bathroom, closet, or interior hallway that is away from corners, windows, doors, and outside walls.

What You Need to Do During a Warning

  • Take shelter immediately; do not stay in a mobile home.
  • Listen to your local radio for updates.
  • Close the windows in your home or business.
  • If you are in a car or other mobile vehicle, get out immediately and go to a nearby sturdy building or storm structure.
  • Do not try to outrun a tornado in a car, and do not park the car under a highway overpass or bridge (the winds are stronger there and you're more susceptible to flying debris).
  • If you are outside without nearby shelter, lie down in a ditch, ravine, or depression and cover your head with your hands.

Common Zones for Tornados

Tornado Alley is where tornados are the most frequent, and these tornados tend to be the most devastating. They are very strong and cover lots of ground at high speeds. This zone includes the states of Texas, Oklahoma, Kansas, South Dakota, Iowa, Illinois, Missouri, Nebraska, Colorado, North Dakota, and Minnesota.

Dixie Alley is more susceptible to precipitation-based tornados or outbreaks of multiple tornados that are part of the same weather system. The area that is known as Dixie Alley includes mostly southeastern states like Arkansas, Louisiana, Mississippi, Tennessee, Alabama, Georgia, South Carolina, North Carolina, and Kentucky.

Tornadoes in the U.S. are most common from March to June, which is known as "tornado season." However, tornadoes can take place at any time of year and destructive tornadoes are on record for every month of the year.

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