Tornadoes & Tornado Safety
Tornadoes are a violent, dangerous column of rotating air extending from a thunderstorm cloud to the ground. Wind speeds in extremely powerful tornadoes can reach up to 300 miles per hour and can be as much as two miles wide. But most tornadoes have wind speeds closer to 100 miles per hour, still very dangerous and destructive.
Tornadoes typically form inside large thunderstorms. Powerful thunderstorms contain columns of strong upward rising motion right next to areas of strong sinking motion. In addition, air tends to flow horizontally into thunderstorms as well. All of these air currents cause chaotic flow inside thunderstorms. Sometimes this chaotic flow can form into spinning funnels of condensed water vapor. These are known as funnel clouds. If the funnel cloud extends down to the ground it becomes known as a tornado. If the funnel touches down over the water it can be known as a water spout.
Tornadoes can occur anywhere in the world. They are most common in warmer climates and when large temperature contrasts exist near boundaries of warm and cold fronts. Tornadoes are quite common in the United States. The area known as Tornado Alley in the Plains, Midwest, Ohio Valley and Southeast is where most strong tornadoes occur. Tornadoes are very common in Florida as well, but typically they are not quite as strong in South Florida. This is because the most extreme tornadoes occur where the largest temperature contrast is present. The strongest tornadoes occur during the spring, because temperature contrasts between warm and cold air masses is greatest between March and June.
Tornado intensity is measured by the Enhanced Fujita (EF) Scale. It ranges from the weaker EF0 where winds are estimated to be 65-85 mph, all the way up to an EF5 (winds can be greater than 200 mph). For more about the EF Scale go to . Most tornadoes are weak, with about 50 percent of all tornadoes rated EF0. Less than one percent rated EF5. EF0 tornadoes typically only cause minor damage, such as broken tree branches and minor damage to roof shingles or sidings. In an EF5 tornado, there is often complete destruction. A storm of EF5 strength can destroy a well-built home and flip over cars and trucks.
Tornadoes can form quickly and are often difficult to see and detect. Weather forecasters rely on eyewitness reports and Doppler radar for information. Typically meteorologists analyze Doppler radar data to alert the public when threatening weather is moving in. Doppler radar allows forecasters to see the speed and direction of winds inside thunderstorms. If rotating winds are detected inside a storm and forecasters believe this rotating air may reach the ground, the National Weather Service will issue a tornado warning. Typically people will only minutes to react and take cover. Tornadoes are not always visible to observers on the ground, especially when the tornadoes are wrapped in rain. People who have experienced a tornado often say that it sounds like a freight train.
Tornado Safety
If a tornado warning is issued for your area, you must react immediately. Tornadoes can form in minutes and move very quickly. If you suspect a tornado may be heading in your direction immediately go to a well constructed building. Once inside, stay away from windows, preferably in an interior room or closet. These smaller rooms are often constructed better and are less exposed to the wind. This reduces the chances of being injured by flying debris, the cause of most tornado-related. If conditions seem to be deteriorating rapidly, get underneath a sturdy desk, inside a bathtub, or on the floor covered with a mattress. If you’re driving, pull over to the side of the road and take cover in a ditch if possible.
Questions:
- Tornadoes form inside thunderstorms. T/F
- Taking cover in a trailer is safe in a tornado. T/F
- Most Tornadoes are EF5 tornadoes. T/F
- Tornadoes are most common in South Florida. T/F
- Meteorologists can predict tornadoes hours before they become a threat. T/F
Links: