The Fujita scale,or Fujita–Pearson scale,is a scale for rating tornado intensity,based primarily on the damage tornadoes inflict on human-built structures and vegetation. The official Fujita scale category is determined by meteorologists and engineers after a ground or aerial damage survey,or both;and depending on the circumstances,ground-swirl patterns,weather radar data,witness testimonies,media reports and damage imagery,as well as photogrammetry or videogrammetry if motion picture recording is available. The Fujita scale was replaced with the Enhanced Fujita scale (EF-Scale) in the United States in February 2007. In April 2013,Canada adopted the EF-Scale over the Fujita scale along with 31 "Specific Damage Indicators" used by Environment Canada (EC) in their ratings.
The 1999 Oklahoma tornado outbreak was a significant tornado outbreak that affected much of the Central and parts of the Eastern United States,with the highest record-breaking wind speeds of 301 ± 20 mph (484 ± 32 km/h). During this week-long event,154 tornadoes touched down. More than half of them were on May 3 and 4 when activity reached its peak over Oklahoma,Kansas,Nebraska,Texas,and Arkansas.
A deadly tornado outbreak occurred in Central Texas during the afternoon and evening of May 27,1997,in conjunction with a southwestward-moving cluster of supercell thunderstorms. These storms produced 20 tornadoes,mainly along the Interstate 35 corridor from northeast of Waco to north of San Antonio. The strongest tornado was an F5 tornado that leveled parts of Jarrell,killing 27 people and injuring 12 others. Overall,30 people were killed and 33 others were hospitalized by the severe weather.
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 on the Fujita Scale,even though tornadoes were not ranked on any scale at the time. It holds records for longest path length at 219 miles (352 km),longest duration at about 3½hours,and it held the fastest forward speed for a significant tornado at 73 mph (117 km/h) anywhere on Earth until 2021. In addition,it is the deadliest single tornado in United States history with 695 fatalities. It was also the third most costly 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.
A destructive and deadly tornado outbreak impacted the Red River Valley on April 10,1979. Several strong to violent tornadoes touched down throughout the region that day. One F4 tornado impacted Vernon,Texas. The most notable tornado was another F4 tornado that destroyed most of the southern part of Wichita Falls,Texas,and is commonly referred to as "Terrible Tuesday" by many meteorologists. Additional tornadoes were reported across the Southern Plains as well as in the Mississippi River Valley on April 11–12. Overall,the outbreak killed 58 people and injured 1,927 others. This tornado outbreak resulted from a storm system that was the same storm system that,just a few days later,produced the 1979 Easter flood,which was the worst disaster to befall Jackson,Mississippi in over a century,causing over $500 million in 1979 dollars,forcing the evacuation of over 15,000 residents,and killing one.
The Enhanced Fujita scale rates tornado intensity based on the severity of the damage they cause. It is used in some countries,including the United States,Canada,China,and Mongolia.
Timothy Patrick Marshall is an American structural and forensic engineer as well as meteorologist,concentrating on damage analysis,particularly that from wind and other weather phenomena. He is also a pioneering storm chaser and was editor of Storm Track magazine.
The Marion,Illinois tornado outbreak was a small,severe tornado outbreak that affected southern portions of the Midwestern United States on May 29,1982.
This page documents the tornadoes and tornado outbreaks of 1999,primarily in the United States. Most tornadoes form in the U.S.,although some events may take place internationally,particularly in parts of neighboring southern Canada during the Northern Hemisphere's summer season,as well as Europe. One particular event,the Bridge Creek-Moore,Oklahoma F5 tornado,produced the highest wind speed ever recorded on Earth,which was 301 ± 20 mph (484 ± 32 km/h).
Tornadoes are more common in the United States than in any other country or state. The United States receives more than 1,200 tornadoes annually—four times the amount seen in Europe. Violent tornadoes—those rated EF4 or EF5 on the Enhanced Fujita Scale—occur more often in the United States than in any other country.
This page documents the tornadoes and tornado outbreaks of 1997,primarily in the United States. Most tornadoes form in the U.S.,although some events may take place internationally. Tornado statistics for older years like this often appear significantly lower than modern years due to fewer reports or confirmed tornadoes,however by the 1990s tornado statistics were coming closer to the numbers we see today.
On the evening of Monday,May 3,1999,a large and exceptionally powerful F5 tornado registered the highest wind speeds ever measured globally;winds were recorded at 301 ± 20 miles per hour (484 ± 32 km/h) by a Doppler on Wheels (DOW) radar. Considered the strongest tornado ever recorded to have affected the metropolitan area,the tornado devastated southern portions of Oklahoma City,Oklahoma,along with surrounding suburbs and towns to the south and southwest. The tornado covered 38 miles (61 km) during its 85-minute existence,destroying thousands of homes,killing 36 people,and leaving US$1 billion in damage,ranking it as the fifth-costliest on record not accounting for inflation. Its severity prompted the first-ever use of the tornado emergency statement by the National Weather Service.
The first six days of December 1953 produced a destructive and deadly tornado outbreak sequence across the Southern United States. There were 19 confirmed tornadoes,including a violent F4 tornado that hit the northwest side of Alexandria,Louisiana and even more violent F5 tornado that hit Vicksburg,Mississippi. In all,the tornadoes killed 49 people,injured 404 others,and caused $45,709 million in damage. This was the last in a series of deadly and catastrophic outbreaks to strike the US in 1953.
On April 27,1971,a violent F4 tornado struck Gosser Ridge and other parts of Russell and Pulaski County,Kentucky. In November 1999,the National Climatic Data Center published a list of the historical F5 tornadoes in the United States from 1880 to 1999,which rated the Gosser Ridge tornado as an F5 tornado. It was later officially downgraded to an F4 tornado.
During the afternoon of June 16,1992,a violent tornado,commonly known as the Chandler–Lake Wilson tornado,tore through the town of Chandler and city of Lake Wilson in Murray County,Minnesota. The damage in Chandler was extreme enough,for the local National Weather Service office to rate the damage F5 on the Fujita scale.
On April 19,1976,a violent tornado struck Brownwood,Texas. The damage caused by the tornado was extreme enough for the National Weather Service to rate the tornado F5 on the Fujita scale. In 1993,meteorologist and tornado expert Thomas P. Grazulis disagreed with the National Weather Service's assessment of the tornado,which he assigned a max rating of F4 on the Fujita scale.
