Tornadoes – Anatomy of a Tornado

Tornadoes – Twisters – Cyclones

The majority of tornadoes occur in Tornado Alley in the United States.

Tornado – a violently rotating column of air that is in contact with both the surface of the earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as twisters or cyclone.

Tornadoes cause damage to homes, business, wildlife and human life. They can happen in daylight or in the middle of the night and there is often little or no warning. Tornadoes come in many shapes and sizes and usually visibly in the form of a funnel. However, some tornadoes are not visible by a funnel cloud. Wind speeds can be less than 110 miles per hour up to speeds of more than 300 miles per hour and can travel a few miles before dissipating. Tornadoes have been recorded in every continent except Antarctica. The majority of tornadoes occur in Tornado Alley in the United States. Although they can occur any time day or night, there is little to no warning. They can be detected before by the use of Pulse Doppler radar and storm chasers.


Tornadoes cause damage to homes, business, wildlife and human life. They can happen in daylight or in the middle of the night and there is often little or no warning. Tornadoes come in many shapes and sizes and usually visibly in the form of a funnel. However, some tornadoes are not visible by a funnel cloud. Wind speeds can be less than 110 miles per hour up to speeds of more than 300 miles per hour and can travel a few miles before dissipating. Tornadoes have been recorded in every content except Antarctica. The majority of tornadoes occur in Tornado Alley in the United States. Although they can occur any time day or night, there is little to no warning. They can be detected before by the use of Pulse Doppler radar and storm chasers.


What is 500 feet across and can travel for 5 miles on ground?

In the US, tornadoes are around 500 feet across and can travel for 5 miles on the ground. But the size and shape can vary. Weak tornadoes can be very narrow as a few feet and stronger ones wider. On May 22, 2004 in Hallam, Nebraska was recorded as being up to 2.5 miles wide on the ground. On May 31, 2013 in El Reno, Oklahoma was recorded as being approximately 2.6 miles wide. That is the widest on record. Path lengths can vary, the longest path recorded was on March 18, 1925. This tornado was recorded to be on the ground continuously for 219 miles and affected parts of Missouri, Illinois and Indiana.


There are several types of tornadoes which include; landspout, waterspout, and multiple vortex tornado. Waterspouts are tornadoes that form over bodies of water and tend to develop in tropical climates closer to the equator. A multiple vortex tornado is where there is a formation of dual funnel clouds. For those that remember the movie “Twister” will remember dual tornadoes that formed over a body of water… the actor in the movie refereed to this as “Twins”, however this can happen on land as well.


Tornado Categories

There are several categories of tornadoes which are measured using the Fuiita Scale or the Enhanced Fuiita Scale, which rates them by the damage they cause . An F0 or EF0 is the weakest category which damages tress but usually no substantial damage to structures. An F5 or EF5 is the strongest category where buildings can be ripped off of their foundations and cause much structural damage. There is also a Torro Scale which ranges from a T0 to a T11, again weakest to most powerful. There is the use of Doppler Radar data, photgrammetry, and cyloidal marks (swirl patterns) which may be used to determine intensity to assign a rating like F3, F5 etc.

“Sounds of a Tornado”

The sound of a tornado is caused by multiple mechanisms. Witnesses report a “wooshing roar, freight train, waterfalls or rushing rapids, or a combination. However the audible sound depends on the atmospheric conditions. Funnel clouds produce sounds, and the interaction with the ground and flying debris contribute to the sound.

“How do we know when a Tornado is coming?”

Attempts to warn of tornadoes began in the mind 20th century in the United States. Prior to the 1950’s the only way to detect a tornado was by someone seeing it on the ground at which time the news of a tornado would not reach local weather stations until after it had dissipated. Today with weather radar we can get advance warning of severe weather. In 1953 it was confirmed that “hook echoes” are associated Meteorologist can detect thunderstorms likely producing tornadoes from miles away. The first public tornado warnings were issued in 1950 and tornado watches in 1952.

Rigorous attempts to warn of tornadoes began in the United States in the mid-20th century. Before the 1950s, the only method of detecting a tornado was by someone seeing it on the ground. Often, news of a tornado would reach a local weather office after the storm.

“Tips to keep your employees and family safe”

Prepare before a Tornado

  • Create a business and family tornado plan that includes where to meet in case of separation. Who is in charge of what tasks that need to be done, such as pets and smaller children. Practice your tornado plan at lease once a year. Make sure you have the necessary insurance to cover your property and belongings. Know your
  • Gather items needed; your emergency kit which includes batteries, flash lights, radio, clothing, shoes etc, first aid kit, water and food. Dont forget items for small children and pets. People are now including helmets such as bicycle or sports helmets in their emergency kits. This will protect your head from falling debris.
  • Have cash on hand, bank ATM’s may not work due to power outages.
  • Fill your gas tank; gas stations may not be open or without power
  • Have all important documents and insurance policies together in your emergency kit. Preferably in a small safe or metal box. Back up and business hard drives in case computers are damaged

During a Tornado

  • Seek shelter. Go to your basement or lowest level in your home. If you do not have a basement go into a closet, bathroom or space under a stairwell or a n area with no windows. Blankets, sleeping bags, and mattereses can be used to protect yourself.
  • Those in mobile homes should seek alternative shelter. Schools, hospitals, or churches offer shelter. Find out and have a plan in the preparing stages of where you will go if a tornado watch and warning has been issued.

After a Tornado Hits

  • Stay together until emergency personnel arrive and stay away from power lines and damaged structure.
  • Watch for broken gass and other objects and dont enter buildings or homes that have heavy damage as they could collapse.

Being prepared is important for any emergency situation. Better to have plans that weren’t used than to have an emergency you weren’t prepared and planned for.

#Prepare2015 #CPR4Biz

Emergencies happen every day. Being prepared ensures businesses and their employees have skills and resources to survive with grace, compassion and success.

Crisis Prevention & Restoration; We are business specialists who assess business vulnerabilities, evaluate hazards, and then use that information to design an all hazards action plan. 415.891.9107