Tornadoes are one of nature's most violent storms. In an average year, about 1,000 tornadoes are reported across the United States. A tornado is defined as a violently rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of 250 m.p.h. or more. Damage paths can be in excess of one mile wide and 50 miles long.
Tornadoes come in all shapes and sizes and can occur anywhere in the U.S. at any time of the year. In the southern states, peak tornado season is March through May, while peak months in the northern states are during the summer.
Although tornadoes occur in many parts of the world, these destructive forces of nature are found most frequently in the United States east of the Rocky Mountains during the spring and summer months.
WHAT CAUSES TORNADOES?
Meteorologists rely on weather radar to provide information on developing storms. The National Weather Service is strategically locating Doppler radars across the country which can detect air movement toward or away from the radar. Early detection of increasing rotation aloft within a thunderstorm can allow lifesaving warnings to be issued before the tornado forms.
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 3:00 p.m. and 9:00 p.m. but have been known to occur at all hours of the day or night.
The average tornado moves from southwest to northeast. Severe thunderstorm warnings are passed to local radio and television stations and are broadcast over local NOAA Weather Radio 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.
NOAA WEATHER RADIO IS THE BEST MEANS TO RECEIVE WARNINGS FROM THE NATIONAL WEATHER SERVICE
The National Weather Service continuously broadcasts updated weather warnings and forecasts that can be received by NOAA Weather Radios sold in many stores. The average range is 40 miles, depending on topography. Your National Weather Service recommends purchasing a radio that has both a battery backup and a tone-alert feature which automatically alerts you when a watch or warning is issued.
What to listen for:
- TORNADO WATCH: Tornadoes are possible in your area. Remain alert for approaching storms.
- TORNADO WARNING: A tornado has blooding, lightning, and hail.
TORNADO SAFETY - WHAT YOU CAN DO
Your National Weather Service, Federal Emergency Management Agency, and American Red Cross educate community officials and the public concerning the dangers posed by tornadoes. YOU can prepare for the possibility of a tornado by learning the safest places to seek shelter when at home, work, school, or outdoors. You should also understand basic weather terms and danger signs related to tornadoes. Your chances of staying safe during a tornado are greater if you have a plan for you and your family, and practice the plan frequently.
Before the Storm:
- Develop a plan for you and your family for home, 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.
- Have a NOAA Weather Radio with a warning alarm tone and battery back-up to receive warnings.
- Listen to radio and television for information.
- If planning a trip outdoors, listen to the latest forecasts and take necessary action if threatening weather is possible.
If a warning is issued or if threatening weather approaches:
- 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 o your area. After you have received the warning or observed threatening skies, YOU must make the decision to seek shelter before the storm arrives. It could be the most important decision you will ever make.
WHO'S MOST AT RISK?
- People in automobiles.
- The elderly, very young, and the physically or mentally impaired.
- People in mobile homes.
- People who may not understand the warning due to a language barrier
TORNADO SAFETY IN SCHOOLS
EVERY School Should Have A Plan!
- Develop a severe weather action plan and have frequent drills.
- Each school should be inspected and tornado shelter areas designated by a registered engineer or architect. Basements offer the best protection. Schools without basements should use interior rooms and hallways on the lowest floor and away from windows.
- Those responsible for activating the plan should monitor weather information from NOAA Weather Radio and local radio/television.
- If the school's alarm system relies on electricity, have a compressed air horn or megaphone to activate the alarm in case of power failure.
- Make special provisions for disabled students and those in portable classrooms.
- Make sure someone knows how to turn off electricity and gas in the event the school is damaged.
- Keep children at school beyond regular hours if threatening weather is expected. Children are safer at school than in a bus or car. Students should not be sent home early if severe weather is approaching.
- Lunches or assemblies in large rooms should be delayed if severe weather is anticipated. Gymnasiums, cafeterias, and auditoriums offer no protection from tornado-strength winds.
- Move students quickly into interior rooms or hallways on the lowest floor.
- Hospitals, nursing homes, and other institutions should develop a similar plan.
TORNADO SAFETY AT HOME
Families should be prepared for all hazards that affect their area. NOAA's National Weather Service, the Federal Emergency Management Agency, and the American Red Cross urge each family to develop a family disaster plan.
Where will your family be when disaster strikes? They could be anywhere - at work, at school, or in the car. How will you find each other? Will you know if your children are safe? Disasters may force you to evacuate your neighborhood or confine you to your home. What would you do if basic services - water, gas, electricity or telephones - were cut off?
Follow these basic steps to develop a family disaster plan:
- Gather information about hazards. Contact your local National Weather Service office, emergency management or civil defense office, and American Red Cross chapter. Find out what type of disasters could occur and how you should respond. Learn your community's warning signals and evacuation plans.
- Meet with your family to create a plan. Discuss the information you have gathered. Pick two places to meet: a spot outside your home for an emergency, such as fire, and a place away from your neighborhood in case you can't return home.
- Post emergency telephone numbers by phones;
- Install safety features in your house, such as smoke detectors and fire extinguishers;
- Inspect your home for potential hazards (such as items that can move, fall, break, or catch fire) and correct them;
- Have your family learn basic safety measures, such as CPR and first aid; how to use a fire extinguisher; and how and when to turn off water, gas, and electricity in your home;
- Teach children how and when to call 911 or your local Emergency Medical Services number;
- Keep enough supplies in your home to meet your needs for at least three days. Assemble a disaster supplies kit with items you may need in case of an evacuation. Store these supplies in sturdy, easy-to-carry containers, such as 5-gallon buckets.
OTHER THUNDERSTORM HAZARDSThese dangers often accompany thunderstorms:
- Flash Floods: Number ONE weather killer - 146 deaths annually.
- Lightning: Kills 75-100 people each year.
- Damaging Straight-line Winds: Can reach 140 m.p.h.
- Large Hail: Can reach the size of a grapefruit - causes several hundred million dollars in damage annually to property and crops.
Contact your local National Weather Service office, American Red Cross chapter, or Federal Emergency Management Agency office for a copy of the "Thunderstorms and Lightning...The Underrated Killers" brochure (NOAA PA 92053) and the "Flash Floods and Floods...The Awesome Power" brochure (NOAA PA 92050).
Look out for:
- Dark, often greenish sky.
- Wall cloud.
- Large hail.
- Loud roar; similar to a freight train.
- Some tornadoes appear as a visible funnel extending only partially to the ground. Look for signs of debris below the visible funnel.
- Some tornadoes are clearly visible while others are obscured by rain or nearby low clouds.
- Stay away from windows.
- Get out of automobiles.
- Do not 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.
IT'S UP TO YOU!
Each year, many people are killed or seriously injured by tornadoes despite advance warning. Some did not hear the warning while others received the warning but did not believe a tornado would actually affect them. The preparedness information in this brochure, combined with timely severe weather watches and warnings, could save your life in the event a tornado threatens as backpacks or duffle bags. Keep important family documents in a waterproof container. Keep a smaller disaster supplies kit in the trunk of your car.
A DISASTER SUPPLIES KIT SHOULD INCLUDE:
- A three-day supply of water (one gallon per person per day) and food that won't spoil.
- One change of clothing and footwear per person.
- One blanket or sleeping bag per person.
- A first-aid kit, including prescription medicines.
- Emergency tools, including a battery-powered NOAA Weather Radio and a portable radio, flashlight, and plenty of extra batteries.
- An extra set of car keys and a credit card or cash.
- Special items for infant, elderly, or disabled family members.
Practice and maintain your plan. Ask questions to make sure your family remembers meeting places, phone numbers, and safety rules. Conduct drills. Test your smoke detectors monthly and change the batteries at least once a year.