Tornado Facts
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Tornadoes are nature's most violent storms. Spawned from powerful thunderstorms, tornadoes can uproot trees, destroy buildings and turn harmless objects into deadly missiles. They can devastate a neighborhood in seconds.A tornado appears as a rotating, funnel-shaped cloud that extends to the ground with whirling winds that can reach 300 miles per hour. Damage paths can be in excess of one mile wide and 50 miles long. Every state is at some risk from this hazard.
Tornado facts
- A tornado is a violently rotating column of air extending from a thunderstorm to the ground.
- Tornadoes are capable of destroying homes and vehicles and can cause fatalities.
- Tornadoes may strike quickly, with little or no warning.
- Tornadoes may appear nearly transparent until dust and debris are picked up or a cloud forms in the funnel. The average tornado moves SW to NE but tornadoes have been known to move in any direction.
- The average forward speed is 30 mph but may vary from stationary to 70 mph with rotating winds that can reach 300 miles per hour.
- Tornadoes can accompany tropical storms and hurricanes as they move onto land.
- Waterspouts are tornadoes that form over water.
- Tornadoes are most frequently reported east of the Rocky Mountains during spring and summer months but can occur in any state at any time of year.
- In the southern states, peak tornado season is March through May, while peak months in the northern states are during the late spring and early summer.
- Tornadoes are most likely to occur between 3 p.m. and 9 p.m., but can occur at any time of the day or night.
Tornados Take Many Shapes and Sizes | Weak Tornadoes | Strong Tornadoes | Violent Tornadoes |
|---|
- 69% of all tornadoes
- Less than 5% of deaths
- Lifetime 1-10+ minutes
- Winds less than 110 mph
| - 29% of all tornadoes
- Nearly 30% of deaths
- Last 20 minutes or more
- Winds 110-205 mph
| - Only 2% of tornadoes
- 70% of all deaths
- Can exceed 1 hour
- Winds 205+ mph
|
Tornado Myths:
- MYTH:
- Areas near rivers, lakes, and mountains are safe from tornadoes.
- FACT:
- No place is safe from tornadoes. In the late 1980's, a tornado swept through Yellowstone National Park leaving a path of destruction up and down a 10,000-ft. mountain.
- MYTH:
- The low pressure with a tornado causes buildings to "explode" as the tornado passes overhead.
- FACT:
- Violent winds and debris slamming into buildings cause most structural damage.
- MYTH:
- Windows should be opened before a tornado approaches to equalize pressure and minimize damage.
- FACT:
- Opening windows allows damaging winds to enter the structure. Leave the windows alone; instead, immediately go to a safe place.
Stay Informed About the Storm:
- By listening to NOAA Weather Radio, commercial radio and television for the latest tornado WATCHES and WARNINGS.
- When conditions are favorable for severe weather to develop, a severe thunderstorm or tornado WATCH is issued.
- Weather Service personnel use information from weather radar, spotters, and other sources to issue severe thunderstorm and tornado WARNINGS for areas where severe weather is imminent.
- Severe thunderstorm warnings are passed to local radio and television stations and are broadcast over local NOAA Weather Radio stations serving the warned areas. These warnings are also relayed to local emergency management and public safety officials who can activate local warning systems to alert communities.
Noaa Weather Radio Is the Best Means to Receive Warnings From the National Weather Service:The National Weather Service continuously broadcasts updated weather warnings and forecasts that can be received by NOAA Weather Radios sold in many stores. The average range is 40 miles, depending on topography. Your National Weather Service recommends purchasing a radio that has both a battery backup and a tone-alert feature which automatically alerts you when a watch or warning is issued.
What to Listen For...
- TORNADO WATCH:
- Tornadoes are possible in your area. Remain alert for approaching storms.
- TORNADO WARNING:
- A tornado has been sighted or indicated by weather radar. If a tornado warning is issued for your area and the sky becomes threatening, move to your pre-designated place of safety.
- SEVERE THUNDERSTORM WATCH:
- Severe thunderstorms are possible in your area.
- SEVERE THUNDERSTORM WARNING:
- Severe thunderstorms are occurring.
Remember, tornadoes occasionally develop in areas in which a severe thunderstorm watch or warning is in effect. Remain alert to signs of an approaching tornado and seek shelter if threatening conditions exist.
Some Environmental Clues: Look out for:
- Dark, often greenish sky
- Cloud of Debris
- Large hail
- Loud roar; similar to a freight train
- Funnel Cloud
Caution: Some tornadoes appear as a visible funnel extending only partially to the ground. Look for signs of debris below the visible funnel. Some tornadoes are clearly visible while others are obscured by rain or nearby low-hanging clouds.
It's Up to YOU!Each year, many people are killed or seriously injured by tornadoes despite advance warning. Some did not hear the warning while others received the warning but did not believe a tornado would actually affect them. The preparedness information on this website, combined with timely severe weather watches and warnings, could save your life in the event a tornado threatens your area. After you have received the warning or observed threatening skies, YOU must make the decision to seek shelter before the storm arrives. It could be the most important decision you will ever make.