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Most tornadoes in the United States form in an area called "Tornado Alley". This area includes parts of Texas, Oklahoma, Kansas, and Nebraska. Storm chasers travel to this area because of the high concentration of tornadoes. These tornadoes are formed by thunderstorms. Some of the tornadoes in the southern states such as Florida, South Carolina, and Georgia are caused by hurricanes.
Georgia, Idaho, Indianna, Ohio, Kentucky, Alabama, Virginia, Texas, Louisiana, Florida Killer tornadoes, National Weather Sevice, National Tornadoes Service, Tornado news, National Tornado Center, Louisiana Homeland Security And Emergency Preparedness, Tornado Headquarters, FEMA Headquarters, FEMA Homeland Security. A tornado is a violent, dangerous, 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 a twister or a cyclone, although the word cyclone is used in meteorology in a wider sense, to name any closed low pressure circulation. Tornadoes come in many shapes and sizes, but are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust. Most tornadoes have wind speeds less than 110 miles per hour (177 km/h), are approximately 250 feet (80 m) across, and travel a few miles (several kilometers) before dissipating. The most extreme tornadoes can attain wind speeds of more than 300 mph (480 km/h), stretch more than two miles (3 km) across, and stay on the ground for dozens of miles (more than 100 km). Various types of tornadoes include the landspout, multiple vortex tornado, and waterspout. Waterspouts are characterized by a spiraling funnel-shaped wind current, connecting to a large cumulus or cumulonimbus cloud. They are generally classified as non-supercellular tornadoes that develop over bodies of water. These spiraling columns of air frequently develop in tropical areas close to the equator, and are less common at high latitudes. Other tornado-like phenomena that exist in nature include the gustnado, dust devil, fire whirls, and steam devil. Tornadoes have been observed on every continent except Antarctica. However, the vast majority of tornadoes in the world occur in the Tornado Alley region of the United States, although they can occur nearly anywhere in North America. They also occasionally occur in south-central and eastern Asia, the Philippines, south east Asia, like Malaysia, northern and east-central South America, Southern Africa, northwestern and southeast Europe, western and southeastern Australia, and New Zealand. Tornadoes can be detected before or as they occur through the use of Pulse-Doppler radar by recognizing patterns in velocity and reflectivity data, such as hook echoes, as well as by the efforts of storm spotters. There are several different scales for rating the strength of tornadoes. The Fujita scale rates tornadoes by damage caused, and has been replaced in some countries by the updated Enhanced Fujita Scale. An F0 or EF0 tornado, the weakest category, damages trees, but not substantial structures. An F5 or EF5 tornado, the strongest category, rips buildings off their foundations and can deform large skyscrapers. The similar TORRO scale ranges from a T0 for extremely weak tornadoes to T11 for the most powerful known tornadoes. Doppler radar data, photogrammetry, and ground swirl patterns (cycloidal marks) may also be analyzed to determine intensity and assign a rating.
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Tornadoes - Louisiana Floods - Texas Tornadoes - Texas Floods - Florida
Tornadoes - Florida Floods
TROPICAL DEPRESSION
An organized system of clouds and thunderstorms
with a defined surface circulation and maximum sustained winds* of 38 mph
or less
TROPICAL STORM
An organized system of strong thunderstorms
with a defined surface circulation and maximum sustained winds of 39-73
mph
HURRICANE
An intense tropical weather system of strong
thunderstorms with a well-defined surface circulation and maximum sustained
winds of 74 mph or higher
What Are The Hurricane Hazards?
STORM SURGE - is water that is pushed toward
the shore by the force of the winds swirling around the storm. This advancing
surge combines with the normal tides to create the hurricane storm tide,
which can increase the mean water level 15 feet or more.
INLAND FLOODING - In the last 30 years, inland
flooding has been responsible for more than half the deaths associated
with tropical cyclones in the United States.
HIGH WINDS - Hurricane-force winds can destroy
poorly constructed buildings and mobile homes. Debris such as signs, roofing
material, and small items left outside become flying missiles in hurricanes.
TORNADOES - Hurricanes can produce tornadoes
that add to the storm's destructive power. Tornadoes are most likely to
occur in the right-front quadrant of the hurricane.
A section of the Great Plains in the central
part of the United States is called "Tornado Alley". This is because more
tornadoes form here than any other part of the country. The plains are
flat which allows cold polar air from Canada to meet warm tropical air
from the Gulf of Mexico.
Storm chasers go Tornado Alley looking for
tornadoes because there are so many that form there.
Tornado alley
Tornadoes have hit all fifty states of
the United States, but the 30-year average number of tornadoes per year
in Alaska is closer to zero than to one. In Oklahoma though the average
jumps to 52. Although no state is immune for tornadoes, there is an area
that suffers from more tornadoes than any other. This area is called Tornado
Alley. It is stretched out from West-Texas to North-Dakota. That is 1600
kilometres from north to south and 950 kilometres from east to west. Because
it is not an official area the areas that are counted for can vary. What
is certain is that large pieces of Texas, Kansas and Nebraska are a part
of it. These areas suffer from more tornadoes than any other state in the
United States.
Louisiana Tornado - Louisiana Floods - Texas Tornado - Texas Floods - Florida Tornado - Florida Floods
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