Tornadoes have been reported in every state. They generally occur during spring and summer, although they can happen in every season. Tornadoes can strike at any time of the day or night but are most likely between 3:00 p.m. and 9:00 p.m. No areas are immune to tornadoes; they have been reported in mountains and valleys, over deserts and swamps, from the Gulf Coast into Canada, in Hawaii, and even in Alaska. Regardless of the location or time of year, if conditions are right, a tornado can develop. More than 1,000 tornadoes are reported annually nationwide, and as our tornado detection systems improve, fewer tornadoes go undetected.

Even so, tornadoes sometimes develop in areas in which no tornado watch or warning has been issued.

A tornado is a violently rotating column of air extending from the base of a thunderstorm to the ground. Tornado intensities are classified on the Fujita Scale with ratings between 0 and 5. A storm of F0 is the weakest and F5 is the strongest. The most violent tornadoes have rotating winds of 250 miles (402 kilometers) per hour or more. These are capable of destroying well-made structures, uprooting trees, and hurling normally harmless objects through the air like deadly missiles. Most tornadoes are rated F0 and F1, and these usually span just a few dozen yards and touch down only briefly. Highly destructive violent tornadoes—F4 and F5—can carve out paths more than a mile (1.6 kilometers) wide and 50 miles (80 kilometers) long. Although these violent tornadoes comprise only two percent of all tornadoes, they are responsible for nearly 70 percent of tornado-related fatalities.

Waterspouts are similar to tornadoes but form over a body of water. They are most common along the Florida Gulf and Atlantic coasts and southeastern states. In the western United States, waterspouts occur in connection with storms in the late fall or winter, a time when they are least expected. Waterspouts occasionally move inland becoming tornadoes, causing damage and injuries.

Each year, many people are killed or seriously injured by tornadoes despite advance warning. Some did not hear the warning, while others heard the warning but did not believe they were personally threatened. Timely tornado watches and warnings, combined with household preparedness, could save your life. Once you receive a warning or observe threatening skies, you must make the decision to take shelter before the tornado arrives. It could be the most important decision you will ever make.


  • Decide where family members, including pets, should gather during a tornado. The safest place to be is underground, or as low to the ground as possible, and away from all windows. If you have a basement or storm cellar, make it your safe place. If you do not have a basement or storm cellar, consider an interior bathroom, closet, or hallway on the lowest floor. Putting as many walls as you can between you and the outside will provide additional protection. Less than two percent of all tornadoes are powerful enough to destroy a sturdy building. Make sure there are no windows or glass doors in your safe place and keep this place uncluttered.
  • If you are in a high-rise building, pick a place in a hallway in the center of the building. You may not have enough time to go to the lowest floor. Center hallways are often the most structurally reinforced part of a building.
  • If you live in a mobile home, choose a safe place in a nearby sturdy building. A sturdy building provides greater protection. If your mobile home park has a designated shelter, make it your safe place. Mobile homes are much more vulnerable to strong winds than site-built structures. Prior to 1994, most mobile homes were not designed to withstand even moderate winds.
  • Learn about your community's warning system. Different communities have different ways of providing warnings. Many communities have sirens intended for outdoor warning purposes.
  • Use a NOAA (National Oceanic & Atmospheric Administration [US]) Weather Radio to keep aware of watches and warnings while you are indoors.
  • Make sure all family members know the name of the county or parish where you live or are traveling, because tornado watches and warnings are issued for a county or parish by name.
  • Conduct periodic tornado drills, so everyone remembers what to do if a tornado approaches. Practice having everyone in the household go to your designated safe place.
  • Have everyone get under a sturdy piece of furniture, hold on with one hand, and protect his or her head and neck with the other. Practicing your plan makes the appropriate response more of a reaction, requiring less thinking time during an actual emergency.
  • Check at your workplace and your children's schools and day care centers to learn about their tornado emergency plans. Every building has different safe places. It is important to know where they are and how to get there in an emergency.
  • Discuss tornadoes with your family. Everyone should know what to do in case not all family members are together. Discussing disaster preparedness ahead of time helps reduce fear and lets everyone know what to do in a tornado situation.

After a Tornado

  • Continue listening to local radio or television stations or a NOAA Weather Radio for updated information and instructions. Access may be limited to some parts of the community or roads may be blocked.
  • Check for injuries. Give first aid and get help for injured or trapped persons. Taking care of yourself first will allow you to help others safely until emergency responders arrive.
  • Help people who require special assistance—infants, elderly people, those without transportation, large families who may need additional help in an emergency situation, people with disabilities, and the people who care for them.
  • Watch out for fallen power lines or broken gas lines and report them to the utility company immediately. Reporting potential hazards will get the utilities turned off as quickly as possible, preventing further hazard and injury.
  • Avoid damaged areas. Your presence might hamper rescue and other emergency operations and put you at further risk from the residual effects of tornadoes.
  • Stay out of damaged buildings.
  • If you are away from home, return only when authorities say it is safe.
  • Wear long pants, a long-sleeved shirt, and sturdy shoes. Cut/injured feet are the most common injury following a disaster.
  • Use battery-powered lanterns or flashlights when examining buildings. Battery-powered lighting is the safest and easiest. It protects the user, the building occupants, and the building from fire hazards. DO NOT USE CANDLES.
  • Examine walls, floors, doors, staircases, and windows to make sure that the building is not in danger of collapsing.
  • Look for fire hazards. There may be broken or leaking gas lines, or damage to electrical systems. Clean up spilled medications, bleaches, gasoline, or other flammable liquids immediately. Fire is the most frequent hazard following other disasters.
  • Check for gas leaks. If you smell, gas or hear a blowing or hissing noise, open a window and get everyone out quickly. Turn off the gas using the outside main valve if you can, and call the gas company from a neighbor's home. If you turn off the gas for any reason, it must be turned back on by a professional.
  • Look for electrical system damage. If you see sparks or broken or frayed wires, or if you smell burning insulation, turn off the electricity at the main fuse box or circuit breaker. If you have to step in water to get to the fuse box or circuit breaker, call an electrician first for advice.
  • Electrical equipment should be checked and dried before being returned to service.
  • Watch for loose plaster, drywall, and ceilings that could fall.
  • Take pictures of the damage, both of the building and its contents, for insurance claims.
  • Use the telephone only for emergency calls. Telephone lines are frequently overwhelmed in disaster situations. They need to be clear for emergency calls to get through.
  • Watch your animals closely. Keep all your animals under your direct control. Your pets may be able to escape from your home or through a broken fence. Pets may become disoriented, particularly because tornadoes and the heavy rains that accompany them will usually affect scent markers that normally allow animals to find their homes. The behavior of pets may change dramatically after any disruption, becoming aggressive or defensive, so be aware of their well-being and take measures to protect them from hazards, including displaced wild animals, and to ensure the safety of other people and animals.