Tornadoes . To scientists who study them, twisters are the most fascinating storms on Earth. Let's say they're right ... and take a gander at the wild, whirling winds.
Tornadoes are unpredictable and deadly--witness the set of twisters that tore through Bangladesh on May 13, killing at least 500 and injuring up to 50,000 people.
Tornadoes are also irresistible, it seems. Stout-hearted storm chasers race to put themselves right in the path of danger, both for the sheer thrill of it and to gather information that will clarify how tornadoes form, gather strength and dissipate. The obsession seems to be catching: thrill-seekers are flocking to see real and imagined tornadoes blast across movie screens throughout the U.S.
- Common Tornado Myths: Leave the windows alone when a tornado may be coming. It's a myth that tornadoes cause houses to explode due to changes in air pressure.
- Anywhere in a low place in the home is safe. The southwest corner of the basement is just as safe as any other corner, or middle, of the basement. The best place to be is away from all windows.
- Tornadoes can happen anywhere, including California and other states in the continental U.S. Tornadoes don't just happen in "Tornado Alley."
- Tornadoes cause a lot of debris to be blown around and you can be hurt by this debris. Getting under a highway overpass is NOT safe.
- Tornadoes do not "suck" houses, cars, cows, or people, up into the funnel. Their strong winds, however, can blow large objects, including cars, hundreds of feet away.
The average Tornado will cut a path about 6 miles long and 140 yards wide. the average length of a Tornado is around 10-15 minutes, moving usually toward the northeast around 35mph. the average windspeed associated with a Tornado is close to 200mph, but with the more violent F4 and F5 Tornados, the winds are approaching 300mph.
Fortunately, only about 2% of the Tornados are F4 and F5. about 1/3 are considered strong, F2 and F3's, but most are weak F0 or F1 Tornados which cause minor wind damage in comparison. in fact, F0 and F1 wind speeds are less than 113mph, which is light enough for a secured mobile home to withstand. F2 and F3's cause most of the damage on a yearly basis, because of their high frequency. but, when F4 and F5 Tornados occur, their damage is catastrophic.
Tornados aren't the only producers of strong damaging winds. heavy downpours will produce a draft known as straight-line winds that usually occur in advance of a storm system. these winds can easily exceed 75mph and can cause damage similar to an F0 or F1 tornado.
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