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From Wikipedia, the free encyclopedia
A map of the tornado paths in the 1974 Super Outbreak
This article lists various tornado records. The most extreme tornado in recorded history was the Tri-State Tornado, which spread through parts of Missouri, Illinois, and Indiana on March 18, 1925. It is considered an F5, though tornadoes were not ranked on any scale in that era. It holds records for longest path length at 219 miles (352 km), longest duration at about 3½ hours, and fastest forward speed for a significant tornado at 73 mph (117 km/h) anywhere on Earth. In addition, it is the deadliest single tornado in United States history with 695 fatalities. It was also the third-costliest tornado in history at the time, but has been surpassed by several others non-normalized. When costs are normalized for wealth and inflation, it still ranks third today.
The deadliest tornado in world history was the Daulatpur–Saturia tornado in Bangladesh on April 26, 1989, which killed approximately 1,300 people. Bangladesh has had at least 19 tornadoes in its history kill more than 100 people, almost half of the total for the rest of the world.
For 37 years, the most extensive tornado outbreak on record, in almost every category, was the 1974 Super Outbreak, which affected a large area of the central United States and extreme southern Ontario in Canada on April 3 and April 4, 1974. Not only did this outbreak feature 148 tornadoes in only 18 hours, but an unprecedented number of them were violent; 7 were of F5 intensity and 23 were F4. During the peak of this outbreak there were 16 tornadoes on the ground at the same time. More than 300 people, possibly as many as 330, were killed by tornadoes during this outbreak. However, this record was later broken during the 2011 Super Outbreak, which resulted in 362 tornadoes and 324 tornadic fatalities.
Among the most violent known meteorological events are tornadoes. Each year, more than 2,000 tornadoes occur worldwide, with the vast majority occurring in the United States and Europe. In order to assess the intensity of these events, meteorologist Ted Fujita devised a method to estimate maximum winds within the storm based on damage caused; this became known as the Fujita scale. At the top end of the scale, which ranks from 0 to 5, are F5 tornadoes. These storms were estimated to have had winds in excess of 261 mph (420 km/h).[nb 1] Following two particularly devastating tornadoes in 1997 and 1999, engineers questioned the reliability of the scale. Ultimately, a new scale was devised that took into account 28 different damage indicators; this became known as the Enhanced Fujita scale. With building designs taken more into account, winds in an EF5 tornado were estimated to be in excess of 200 mph (320 km/h).
Since 1950, there have been 59 officially rated F5 and EF5 tornadoes in the United States and 1 F5 in Canada. Additionally, the works of tornado expert Thomas P. Grazulis revealed the existence of several dozen more between 1880 and 1995. Grazulis also put into question the ratings of several currently rated F5 tornadoes. Outside the United States and Canada, seven tornadoes have been rated F5: two each in France, Germany, and Italy and one in Russia. Several other tornadoes are also documented as possibly attaining this status.
tornadao, hurricane, storm, typhoon, Powerful Tornado, big cell storm,
From Wikipedia, the free encyclopedia
For other uses, see Dust devil (disambiguation).
A dust devil in Arizona.
Sign Whirlwind of dust forming.
Effect Dust spread in surrounding area, possibly coughing.
A dust devil in Kraków, Poland.
A dust devil is a strong, well-formed, and relatively long-lived whirlwind, ranging from small (half a meter wide and a few meters tall) to large (more than 10 meters wide and more than 1000 meters tall). The primary vertical motion is upward. Dust devils are usually harmless, but can on rare occasions grow large enough to pose a threat to both people and property.
They are comparable to tornadoes in that both are a weather phenomenon of a vertically oriented rotating column of wind. Most tornadoes are associated with a larger parent circulation, the mesocyclone on the back of a supercell thunderstorm. Dust devils form as a swirling updraft under sunny conditions during fair weather, rarely coming close to the intensity of a tornado.