Tornado Warning Signs

Photo: PedalFreak/Flickr.

Whirling dust and debris. Snapping power lines. A continuous rumble or roar often compared to a freight train. And that feared funnel.

Tornadoes are nature’s most violent storms. Yet, many of us don’t know when it’s time to take tornado warning signs seriously enough to start crouching in the tub or in the basement covered by a mattress. Maybe we’ve experienced a tornado drill in school. But most of us have never and will never see a twister, except in “The Wizard of Oz.”

Although severe tornadoes are more common in the plains states, tornadoes have been reported in every state, according to the American Red Cross. There were more tornadoes this past April — 750 — than any other month in U.S. history, says Greg Carbin, warning coordinator meteorologist for the storm prediction center of the National Oceanic and Atmospheric Administration’s National Weather Service.

“Tornadoes are small-scale events, part of a larger scale weather system,” Carbin says.

They are usually no more than a half-mile wide and move very rapidly west to east or southwest to northeast, preceded by large hail or heavy rain, he says. The likelihood of experiencing a tornado is very small, but it’s always best to be prepared and not put yourself in a risky position, Carbin advises.

“The most violent tornadoes can level and blow away almost any house and its occupants,” the NOAA reports. “Extremely violent F5 tornadoes are very rare, though. Most tornadoes are actually much weaker and can be survived.”

Taking precautions means understanding tornado warning signs. How many of us know blue-green flashes on the ground near a thunderstorm mean power lines are being snapped by very strong winds, indicating a possible tornado? Or that many tornadoes are wrapped in so much heavy precipitation or hail they can’t be seen? Those are among the warning signs listed by the NOAA/NWS storm prediction center.

Here are 10 less familiar warning signs and tips for preparing once a tornado is imminent:

  • Know the difference between a tornado watch and a warning. A watch means tornadoes are possible in and near the watch area, the Red Cross reports. A warning means a tornado has been sighted or indicated by weather radar. Take shelter immediately.
  • Review and discuss your emergency plans with your family and check supplies, including non-perishable food, water, flashlights, batteries and a weather radio.
  • Prepare to head to a reinforced safe room, basement, storm cellar or interior space — closet, hallway or bathroom — on the lowest level of your home away from windows.
  • Look for dark, often greenish clouds, a reflection of ice and water or hail, that might form a wall or isolated lowering at the base of a thunderstorm.
  • Be aware of hail or heavy rain followed by either dead calm or a fast, intense wind shift.
  • Don’t open windows despite notions that it equalizes the pressure in the house.
  • Remove diseased and damaged limbs from trees. Move or secure large furniture, trash cans, hanging plants or other objects that could become projectiles.
  • Know where heavy objects rest on the floor above (pianos, refrigerators, waterbeds, etc. and avoid shelter below them. They may fall down through a weakened floor and crush you, the NOAA warns.
  • If flying debris occurs while you are driving, pull over and park. Decide whether you feel safe staying in your car with the seat belt on, with your head down below the windows covered by your hands and a blanket, the American Red Cross says. Or if you can, get to a noticeably lower level of the roadway away from cars and trees and lie flat, covering your head with your hands. Carbin says there’s a difference of opinion about which option is safer. There are stories of survival and death with each scenario, so drivers have to use their best judgment based on their particular situation, he says.
  • Plan places your family will meet both within and outside your immediate neighborhood.

Your family may not be together when disaster strikes, so it is important to know how you will contact one another, how you will get back together and what you will do in case of any emergency.

It may be easier to make a long-distance phone call than to call across town, so an out-of-town contact may be in a better position to communicate among separated family members.

If your community experiences a tornado or disaster, register on the American Red Cross Safe and Well website,, or call 1-866-GET-INFO to let your family and friends know your welfare.