The average of tornadoes reported in a year is 800 with 80 deaths and over 1,500 injuries.Tornadoes are very dangerous winds that reach from the ground to the air.
Tornadoes are capable of making tremendous damage with 250 mph winds or more.Damage paths can be one mile wide and fifty miles long.
69% of tornadoes are,weak 29% are strong and 2% are violent tornadoes.
No place is safe from a tornadoes in fact a tornado swept through Yellowstone National Park leaving a path of destruction up and down a 10,000ft. mountain.
Violent winds and debris slamming into buildings cause most structural damage.
The Enhanced F-scale still is a set of wind estimates (not measurements) based on damage.
It uses three-second gusts estimated at the point of damage based on a judgment of 8 levels of damage to 28 indicators.
These estimates vary with height and exposure.
Important note: The 3 second gust is not the same wind as in standard surface observations.
Standard measurements are taken by weather stations in open exposures, using a directly measured, "one minute mile" speed.
The scale uses actual damage to determine a tornado’ s wind speed.

Hurricanes can also produce tornadoes that add to the storm's destructive power.
Tornadoes are most likely to occur in the right-front quadrant of the hurricane.
However, they are also often found elsewhere embedded in the rainbands, well away from the center of the hurricane.

Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability, and (2) wind shear present in the lower atmosphere.
Instability refers to warmer and more humid than usual conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere.
wind shear in this case refers to the wind direction changing, and the wind speed increasing, with height.
An example would be a southerly wind of 15 mph at the surface, changing to a southwesterly or westerly wind of 50 mph at 5,000 feet altitude.
On an average, approximately 800 tornadoes are reported in various parts of the United States every year.

Waterspout tornadoes

Waterspouts are similar to tornadoes, but they form in a different manner.
Water spouts can start as tornadoes over land. If they move over a body of water, they are classified as tornadic.
This type of waterspout can be fairly destructive.
The second type of waterspout is formed over water initially due to warm temperatures in the lower atmosphere along with high humidity.
Fair weather waterspouts are generally not as dangerous and are more com m on than tornadic waterspouts.
However, boaters and people who live near larger bodies of water should take waterspout warnings and watches very seriously.
They form when high layers of cool air blow across a body of water while warm moist air sweeps up from below.
Similar to tornadoes, waterspouts are often seen in groups. Ships out on the ocean have reported as many as 30 in one day!
In Montreal, a waterspout once carried lizards and rained them on the hapless Canadians.
They have sent showers of tadpoles in New York, and even toads in France.
One in Providence, Rhode Island, rained fish down on the people, who promptly collected and sold them.
Waterspouts appear most often from May to September over warm ocean water.
They are usually not as dangerous as tornadoes, but can still cause serious damage to ships.


Fire tornadoes

There are certain conditions in which fires are formed, like when warm air and convergence are present, when such a thing takes place this fire obtains vertical vorticity and forms a funnel, or whirl that is like a tornado.
This fire tornado sweeps about 10 feet wide very much like a wind tornado.
Whirlwinds that is what many of these tornadoes are!
An extreme example is the 1923 great Kanto earthquake in Japan which ignited a large city-siz ed firestorm and produced a gigantic fire whirl that killed 38,000 in fifteen minutes in the Hifukusho-Ato region of Tokyo.
Another example is the numerous large fire whirls (some tornadic) that developed after lightening struck an oil storage facility near San Luis Obispo, California on April 7, 1926, several of which produced significant structural damage well away from the fire, killing two.
Thousands of whirlwinds were produced by the four-day-long firestorm coincident with conditions that produced severe thunderstorm, in which the larger fire whirls carried debris 5 kilometers (3 mi) away.
Most of the largest fire whirls are spawned from wildfires. They form when a warm updraft and convergence from the wildfire are present.
They are usually 10-50 meters (30-200 ft) tall, a few meters (~10 ft) wide, and last only a few minutes.
However, some can be more than a kilometer (0.6 mile) tall, contain winds over 160 km/h (100 mph), and persist for more than 20 minutes.

Land spouts

A land spout, or dust-tube tornado, is a tornado not associated with a mesocyclone.
The name stems from their characterization as a "fair weather waterspout on land".
Waterspouts and land-spouts share many defining characteristics, including relative weakness, short lifespan, and a small, smooth condensation funnel which often does not reach the surface.
Land spouts also create a distinctively laminar cloud of dust when they make contact with the ground, due to their differing mechanics from true mesoform tornadoes.
Though usually weaker than classic tornadoes, they can produce strong winds which could cause serious damagetornado_1518021i.jpg.

Mufti-vortex tornadoes

A multiple-vortex tornado is a type of tornado in which two or more columns of spinning air rotate around a common center. Multivortex structure can occur in almost any circulation, but is very often observed in intense tornadoes.
These vortices often create small areas of heavier damage along the main tornado path.
This is a distinct phenomenon from a satellite tornado, which is a weaker tornado which forms very near a large, strong tornado contained within the same mesocyclone. The satellite tornado may appear to orbit the larger tornado (hence the name), giving the appearance of one, large multi-vortex tornado. However, a satellite tornado is a distinct circulation, and is much smaller than the main funnel.
Suction vortices (or suction spots) are really substructures of many, perhaps all, tornadoes but are not always easily visible. These occur, usually, at the base of the tornado vortex where the tornado makes contact with the surface.
Subvortices tend to form after vortex breakdown reaches the surface and are resultant from the ratio of cyclonically incoming and rising air motions.
Multivortex structure is not unique to tornadoes, occurring in other circulations such as dust devils, but is a natural result of the physics of vortex dynamics.