The United States receives the highest number of tornadoes in any given year than any other part of the globe. Tornado occurrences in the US are largely attributed to the warm wet winds from the Gulf of Mexico colliding with the cold dry air from the Canadian front. The recording of tornadoes began back in the 11th century when the first tornado was recorded in Ireland, Europe. Different aspects such as the height, width, and destruction effect are used in determining the largest tornados.
Formation of Tornados
A tornado is a powerful column of winds rotating around a center of low pressure. Tornados are the most treacherous storms occurring from unusually violent thunderstorms. They occur when there are remarkably warm and humid conditions in the lower atmosphere coupled with extremely cooler conditions in the upper atmosphere. Since the warm air is trapped beneath the cold air and cannot rise above the cold air barrier it begins to rotate. As ground temperatures rise, more warm air rises until it breaks through the cold air barrier to trap the cold air beneath. The process creates a cyclonical column with widths of up to 10 miles while rotating anti cyclonically at speeds of up to 200 mph and above.
Tornados were initially ranked by the speed of wind on the Fujita scale, invented by a Japanese-born American meteorologist who specialized in severe storms. In 2007, the scale was advanced to the Enhanced Fujita Scale ranging from EF0 to EF5. At EF0, the winds range at 85 mph and such tornadoes are less severe and destructive. An EF5 tornado is devastating with winds ranging from 200 mph and above. Due to its high magnitude, in terms of speed, width, and duration, it is destructive and annihilated. It leads to massive destruction of property and loss of lives in the affected region.
The Largest Recorded Tornadoes
By width, the El Reno, Oklahoma tornado in May 2013 was the largest recorded tornado. At its peak, the tornado was 2.6 miles and 296 mph at EF5 on the Fujita scale. However, it was later downgraded to EF3 since the winds did not result in any form of destruction in the largely rural area west of Oklahoma City.
Bridge Creek-Moore Tornado occurring in the southern Oklahoma City metro area in May 1999 was the highest wind speed tornado. The winds were measured at a speed of 302 mph rising to a peak of 330ft above the ground, which was the highest wind speeds ever recorded on earth.
The Tri-state tornado was the longest-known track for a single tornado with a path length of up to 235 miles lasting for about 3.5 hours. It was also recorded as the as the fastest forward moving tornado with a speed of 73 mph.
Deadly tornadoes with massive destruction effects have been recorded with the most devastating one occurring in Bangladesh. In April 1989 where 1,300 people lost their lives and property was destroyed. The Joplin tornado in May 2011, was considered the costliest tornado with estimated damages of $2.8 billion.