Tornadoes extend from severe thunderstorms and usually develop from the trailing end of a storm. The air may become very still before one hits. It is also not uncommon for the sun to be visible or partially clear skies during a tornado. Some are easily seen and detected, while others strike quickly with little or no warning.
Some warning signs of a tornado include: strong winds with cloud-base rotation, whirling dust and debris, hail and/or heavy rain, and a loud rumble or roar that sounds similar to a moving train.
If it is nighttime, look for bright blue- or green-colored flashes near the ground. That is an indication of snapped power lines, and an almost sure sign of intense wind or a tornado.
Two of the most fundamental precautions that you can take in the event of a tornado, no matter where you are, is staying low to or below the ground in an interior space away from windows and covering your head with your hands and arms.
It is a good idea to prepare a shelter in advance. If you live between the Rockies and the Mississippi River and are building or buying a house, it is highly advisable that you find or build a home with either a storm cellar or an interior, windowless room close to or below the ground. Store a radio or small TV, as well as padded blankets or a mattress near or in this room.
It is also a good idea for your family to select a place to meet following any tornado or storm in case you are separated at the time of the incident.
Phone lines or other modes of communication may be affected by the storm and are not always reliable.
Mobile homes and dwellings without basements or foundations are not a safe place to be in a tornado. If your community does not have a storm shelter, seek a sturdy building nearby. If there is no time, seek a closet or climb into the bathtub and cover yourself some sort of thick padding, such as a mattress or blankets.
If you live in a house with a finished basement, corner rooms or bathrooms and closets offer extra protection. The more concrete walls or plumbing around you, the better. This reduces the risk of your home caving in on you and better protects you from flying debris.
If you are in a high-rise building, such as a skyscraper, apartment building or dormitory, go to the lowest level or the most interior part of the building you can find. Avoid elevators and stay away from windows.
One of the worst places to be in the event of a tornado is in a vehicle.
Tornadoes generally track from southwest to northeast or from west to east.
Drive in a right angle to the storm and get a considerable distance away.
However, occasionally tornadoes can take an unpredictable turn in any direction. If the storm is approaching fast, park your car quickly and seek a sturdy building or ditch. Do not stay near any vehicles, as they can easily be picked up and dropped by the tornado.
Story by AccuWeather.com News Correspondent Gina Cherundolo