As if super tornadoes and tornado outbreaks are not frightening enough, ever heard of twin tonradoes? Of course, if you’re a tornado chaser, looking for the ultimate thrill, you can’t do much better than twins.
A June 2010 report of a twister splitting–making a twin tornado– came from Ellendale, Minnesota. Ellendale is a small town in the southeastern corner of the state. As reported in the Owatonna People’s Press, the Ellendale Ambulance director reported a “large tornado” that split in two. It goes on to state that the twins damaged or destroyed 49 structures in the Ellendale area.
Palm Sunday Twin Tornado
Sightings of twin tornadoes are rare and footage of them even rarer. The most famous twin tornado image, or perhaps of all tornado images, comes from the devastating 1965 Palm Sunday tornado outbreak. The infamous image, taken by Paul Huffman of the “Elkhart Truth”, shows the massive twins whirling on each side of a street near the town of Elkhart in Northern Indiana.
Twin tornadoes happen when one tornado somehow splits, creating two whirling terrors. In the case of the infamous Elkhart County Palm Sunday twins, the twisters were with 200 feet of each other. The vast majority of tornadoes spin counterclockwise-or cyclonic-in the case of the Elkhart twins, one spun cyclonic, while the other spun the opposite direction in an anti-cyclonic fashion. They tore through a trailer park and an airport, killing 10 people. According to the Northern Indiana National Weather Service, an airplane wing sat about 25 miles away from the end of the twin tornadoes’ path.
Twin Tornado Formation
Meteorologists don’t understand the formation of twin tornadoes as even understanding of traditional single tornado formation is incomplete. Understanding of the formation of a mesocylcone, the pre-cursor to tornado formation, is quite developed. The American Meteorological Society defines a mesocyclone as “a cyclonically rotating vortex, around 2-10 km in diameter, in a convective storm.” Indications of a persistent mesocyclone prompt tornado warnings by the United States National Weather Service.
There are theories of why some storms with mesocyclones produce tornadoes,while others don’t, though no theory is widely accepted. The understanding of tornado formation is hoped to increase through endeavors such as project VORTEX.
The Vortex projects bring swarms of scientists to converge on tornado outbreaks in the Great Plains to gather data. One VORTEX project took place in the spring of 1994 and 1995 while the most recent was in June of 2010.
Let’s hope twin tornadoes remain a rarity and scientists learn all they can to give adequate warning times when tornado outbreaks occur.
American Meteorological Society
Glossary of Meteorology
Northern Indiana National Weather Service
The Palm Sunday Story: Indiana
Tornadoes strike Blooming Prairie, Ellendale; one killed in Albert Lea