Lesser tactics like deploying huge piles of dry ice or smaller conventional weaponry would be too hard to get into the right place fast enough, and would likely not have enough impact to affect the tornado much anyway. Thunderstorms, and all of the hazards they produce, are part of a natural earth cycle. Taking actions sufficient to disrupt this cycle could lead to unintended consequences. What is the difference between a tornado watch and a tornado warning?
A tornado watch defines an area where tornadoes and other kinds of severe weather are possible in the next several hours. It means that you need to be alert, and be prepared to go to safe shelter if tornadoes happen or a warning is issued. Tune in to local TV, radio or internet for more information.
A tornado warning means that a tornado has been spotted, or that Doppler radar shows a thunderstorm circulation which can spawn a tornado. When a tornado warning is issued for your area, seek safe shelter immediately. The Storm Prediction Center issues tornado and severe thunderstorm watches. Your local National Weather Service office issues tornado warnings, as well as thunderstorm warnings, which include the possibility of tornadoes.
What would it be like to be in the eye of a tornado? This is a fiction largely caused by the movie Twister. How many tornadoes hit the US each year? About , though it can vary significantly from year to year or location to location. I have a theory about tornadoes; who do I talk to? We receive literally hundreds of ideas for observing, controlling, or stopping destructive storms.
Our scientists are likely to look at ideas that are investigated by a researcher who publishes the results in a peer-reviewed journal.
In this way they can review, and if necessary, replicate the results, which then will suggest the next step to move the science forward. I would like to volunteer to help NSSL during a tornado intercept field project.
Unfortunately, government regulations make it impossible to accept offers from the public to do volunteer field work for any tornado intercept programs. Legal liability questions prevent NSSL from accepting volunteers, even at their own risk. How is the strength of a tornado determined?
The rating scale for tornadoes is based entirely on the damage they cause. From the damage, we can estimate the wind speeds.
The EF-Scale takes into account more variables than the original Fujita Scale F-Scale when assigning a wind speed rating to a tornado, incorporating 28 damage indicators such as building type, structures and trees. For each damage indicator, there are 8 degrees of damage ranging from the beginning of visible damage to complete destruction of the damage indicator.
The original F-scale did not take these details into account. The original F-Scale historical data base will not change. An F5 tornado rated years ago is still an F5, but the wind speed associated with the tornado may have been somewhat less than previously estimated. Strong or violent tornadoes can and do occur in areas where minimal damage occurs, leading to a low EF scale rating. Do tornadoes target mobile home parks?
While it may appear tornadoes target mobile home parks, they actually do not. Mobile homes are, in general, much easier for a tornado to damage and destroy than well-built houses and office buildings.
A mobile home, or manufactured home, by definition, is built at a factory and taken to the place they will occupy, so they are much more affordable than a house built on-site. They are often built with lighter-weight materials, which do not hold up well in tornadic winds. Straight-line winds can also destroy a mobile home as easily as a tornado, especially one that is not anchored. Any wind gust that is sustained for 3 seconds over 50 mph can cause damage to mobile homes.
The problem of warning and sheltering mobile home residents has become the biggest obstacle to continuing to reduce death tolls from tornadoes. On average, the U. A ten-state area of the Midwest has been named "Tornado Alley" in recognition of its attractiveness to tornadoes. However, tornadoes can occur in any state. In , Alabama was struck particularly hard, with tornadoes rated EF-5 the most intense on the Enhanced Fujita scale hitting Hacklesburg and Birmingham.
Imagery from GOES enabled weather forecasters to foresee the trouble that was about to hit Alabama. Click image for animation. With most weather events, even hurricanes, you know what to expect. The weather forecast will give you a few hours' warning and some idea of what is coming. This information is thanks partly to hard-working satellites that keep a constant eye on the weather.
However, predicting tornadoes precisely is a different story. One minute it's just raining or hailing, and the next minute the roof or even the whole house is gone. EFO mph. Moderate damage: Trees snapped; mobile home pushed off foundations; roofs damaged. EF1 mph. Considerable damage: Mobile homes demolished; trees uprooted; strong built homes unroofed. EF2 mph. Severe damage: Trains overturned; cars lifted off the ground; strong built homes have outside walls blown away.
EF3 mph. If there are enough rising and sinking gusts, the air near the ground starts spinning. This happens in the same way that figure skaters spin faster when their arms are drawn in rather than when their arms are outstretched. This is called conservation of angular momentum. The rotating air moves horizontally across the land, and can be tilted vertically by the force of the rising, rotating air.
That allows a tornado to form.
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