1. TornadoesMargaret Loik & Aleksandra Ruutsaar
2. • A tornado is a violently rotating column of air that is in contact with both the surface of the earth and a cloud .• They are often referred to as twisters or cyclones.• Tornadoes come in many shapes and sizes, but they 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 about 250 feet (76 m) across, and travel a few miles (several kilometers) before dissipating.• The most extreme tornadoes can attain wind speeds of more than 300 miles per hour (483 km/h), stretch more than two miles (3.2 km) across, and stay on the ground for dozens of miles (more than 100 km).
3. Tri-State TornadoThe Great Tri-State Tornado of Wednesday,March 18, 1925, was the deadliest tornado inU.S. history. Inflicting 695 fatalities, the tornadokilled more than twice as many as the seconddeadliest, the 1840 Great Natchez Tornado.The continuous 352 km track left by thetornado was the longest ever recorded in theworld: the tornado crossed from southeasternMissouri, through southern Illinois, then intosouthwestern Indiana.Snapping not only treesand houses in its wake, this Tornado snappedrecords for wind speed, length of path andduration.The Tri-State tornado waltzed its way through atotal of 10 cities, leaving 6 of them completelyin ruins, and severely damaging the other 4.Massive amounts of dust and debris hid thetornados base and funnel and preventedpeople from seeing the massive tornadoapproaching
4. Great Natchez TornadoThe Great Natchez Tornado hit Natchez, Mississippi on May 7, 1840. Itis the second deadliest single tornado in United States history, killing317 people It is also the only recorded massive tornado in the U.S.A.that killed more people than it injured: only 109 were injured. TheFujita scale rating of this tornado is almost certainly an F5 but sincethere was no Fujita scale at the time, this tornado remainsuncategorized.The tornado formed southwest of Natchez, shortly before 1 p.m., andmoved northeast along the Mississippi River.The vortex then struck the river port of Natchez Landing, located belowthe bluff from Natchez. The mile-wide tornado tossed 60 flatboats intothe river, drowning their crews and passengers. A piece of a steamboatwindow was reportedly found 30 miles (50 km) from the river. Manydoing business onshore were also killed. At Natchez Landing, thedestruction of dwellings, stores, steamboats and flatboats was almostcomplete.
5. Daulatpur-Saturia tornado The Daulatpur-Saturia, Bangladesh Tornado was an extremely destructive tornado that occurred in the Manikgonj District, Bangladesh on April 26, 1989. It was the costliest and deadliest tornado in Bangladeshs history. There is great uncertainty about the death toll, but estimates indicate that it killed around 1,300 people, which would make it the deadliest tornado in history. The tornado affected the cities of Daulatpur and Salturia the most, moving east through Daulatpur and eventually northeast and into Saturia. Previously, the area that the tornado hit had been in a state of drought for six months, possibly generating tornadic conditions. Damage was extensive over the area, as countless trees were uprooted and every home within a six square kilometer area of the tornados path was completely destroyed. After the storm hit, an article in the Bangladesh Observer stated that "The devastation was so complete, that barring some skeletons of trees, there were no signs of standing infrastructures". The tornado was estimated to be approximately one mile wide, and had a path that was about 50 miles long, through the poor areas and slums of Bangladesh. Approximately 80,000 people were left homeless by the storm, and 12,000 people were injured by the storm. Saturia and Manikgonj were both fully destroyed by the tornado. The Fujita scale rating of this storm is unknown due to poor housing construction and lack of data. In Bangladesh, housing construction in the poor areas is very poor, so sometimes a strong gust of wind may knock over a home and kill the residents inside. This is also why the vast majority of homes hit by the tornado were leveled
6. The 2011 Joplin tornadoThe 2011 Joplin tornado was a catastrophic EF5multiple-vortex tornado that struck Joplin, Missouri inthe late afternoon of Sunday, May 22, 2011. It was partof a larger late-May tornado outbreak sequence andreached a maximum width of nearly 1 mile (1.6 km)during its path through the southern part of the city.A total of 158 people were killed by the tornado andover 1,100 injured. It was the deadliest tornado inAmerica since 1947.The insurance payout is expected to be $2.2 billion; thehighest insurance payout in Missouri history, higherthan the previous record of $2 billion in the April 10,2001 hail storm.
7. 1999 Oklahoma tornado outbreakThe second most expensive tornadooutbreak in U.S. history and the deadliestof the year occurred May 3–4, 1999, inOklahoma and Kansas. In less than 21hours, a total of 74 tornadoes toucheddown across the two states, with as manyas four tornadoes from different storms onthe ground at once.An F-5 tornado, the strongest on the FujitaTornado Scale, moved along a 61-km path,from Chickasha through south OklahomaCity and the suburbs of Bridge Creek,Newcastle, Moore, Midwest City, and DelCity. With 8,000 buildings damaged, theOklahoma City tornado is the second mostexpensive single tornado in history, causingabout a 2 billion dollars in damage. In all,the tornadoes killed 46 people, injured 800,and caused $1.5 billion in damage.
8. The May 2007 Tornado Outbreak• The May 2007 Tornado Outbreak was an extended tornado outbreak that started on May 4, 2007, affecting portions of the Central United States.• The most destructive tornado in the outbreak occurred on the evening of May 4 in western Kansas, where about 95% of the city of Greensburg in Kiowa County was destroyed by an EF5 tornado.• The super cell killed at least 13 people including 11 in Greensburg and two from separate tornadoes.• At least 60 people were injured in Greensburg alone. It was the strongest tornado of an outbreak which included several other tornadoes reported across Oklahoma, Colorado, Kansas and South Dakota that occurred on the same night. 25 tornadoes were confirmed that night.• The outbreak did not end there; a total of 84 tornadoes were confirmed reported on May 5 in the same area• Damages:$268 million The center of Greensburg, Kansas, twelve days after being hit by the 2007 tornado
9. Tornadoes are classified into 5 different categoriesdepending on wind speed. The 5 categories are : DamageScale Km/H Miles/H Frequency path(meters)F0 64-116 40-72 38.9% 10-50F1 117-180 73-112 35.6% 30-150F2 181-253 113-157 19.4% 110-250F3 254-322 158-206 4.9% 200-500F4 333-418 207-260 1.1% 400-900F5 419-512 261-318 <0.1% >900