A tornado is a spinning column of air connected with both the Earth and clouds simultaneously. The most common cloud that is part of this event is the cumulonimbus cloud, which is tall and dense, and usually associated with thunderstorms. Tornadoes come in a range of wind speeds from under 110 mph to over 300 mph; the highest wind speeds being the rarest. Their life spans run the gamut of a minute to over an hour; the longest times, also, being the rarest. Their diameter is usually about 250 feet, but they can be over two miles wide. These storms are most frequently seen in the United States, east of the Rocky Mountains, but they can also occur to the right and ahead of the storm center of a hurricane.
Science has not come to a consensus as to how tornadoes are formed, but many believe that when cold and warm are present at the same time with the warm, moist air on the bottom being met by cool air coming from an east ward bound cold front above it tornado producing weather can occur. As the warm air tries to rise, if the biometric pressure is low enough, the conditions for a tornado have been met. Also, when warm, moist air is met by hot, dry air moving in from the west a dryline can be created; also, a tornado producing condition.
Tornadoes and thunderstorms usually go together. Before a thunderstorm is formed, the wind direction changes, picks up speed, and the wind travels upward. As it’s rising, the horizontally spinning air enters the thunderstorm and effects the lower atmosphere, lifting the horizontal spinning air until it becomes vertical. When the thunderstorm starts and the spinning becomes vertical its circumference increases adding to the increased circumference of the rotating winds, which can now expand from 2 to 6 miles in width. A lower area in the cloud base is formed and in the rotating area forms a rotating wall cloud, rarely containing rain, which expands into a tornado turning the sky dark with its signature green color. These storms are usually accompanied with additional winds and hail.
You cannot outrun a tornado. If you are in your car find a sturdy structure if there is time, if not, get into a low area not likely to flood and lie down as flat as possible protecting your face and neck. It is particularly important to avoid waiting under an underpass. Mobile homes are not considered sturdy and their residents need to plan ahead for a safe place to wait out such a storm. The best part of a sturdy building is its interior rooms at the buildings lowest level away from windows.