Anticyclonic tornado

From Wikipedia the free encyclopedia

An anticyclonic tornado is a tornado which rotates in a clockwise direction in the Northern Hemisphere and a counterclockwise direction in the Southern Hemisphere.[1] The term is a naming convention denoting the anomaly from normal rotation which is cyclonic in upwards of 98 percent of tornadoes.[citation needed] Many anticyclonic tornadoes are smaller and weaker than cyclonic tornadoes, forming from a different process, as either companion/satellite tornadoes or nonmesocyclonic tornadoes.[2]

An anticyclonic tornado near Big Spring, Texas on May 22, 2016 captured by storm chaser Aaron Jayjack.

Formation[edit]

Most strong tornadoes form in the inflow and updraft area bordering the updraft-downdraft interface (which is also near the mesoscale "triple point") zone of supercell thunderstorms. The thunderstorm itself is rotating, with a rotating updraft known as a mesocyclone, and then a smaller area of rotation at lower altitude the tornadocyclone (or low-level mesocyclone) which produces or enables the smaller rotation that is a tornado. All of these may be quasi-vertically aligned continuing from the ground to the mid-upper levels of the storm. All of these cyclones and scaling all the way up to large extratropical (low-pressure systems) and tropical cyclones rotate cyclonically. Rotation in these synoptic scale systems stems partly from the Coriolis effect, but thunderstorms and tornadoes are too small to be significantly affected. The common property here is an area of lower pressure, thus surrounding air flows into the area of less dense air forming cyclonic rotation. The rotation of the thunderstorm itself is induced mostly by vertical wind shear, specifically clockwise turning as altitude increases (called a veered vertical profile, although backed profiles can occur with anticyclonic supercells).

Various processes can produce an anticyclonic tornado. Most often they are satellite tornadoes of larger tornadoes which are directly associated with the tornadocyclone and mesocyclone. Occasionally anticyclonic tornadoes occur as an anticyclonic companion (mesoanticyclone) to a mesocyclone within a single storm. Anticyclonic tornadoes can occur as the primary tornado with a mesocyclone and under a rotating wall cloud. Also, anticyclonic supercells (with mesoanticyclone), which usually are storms that split and move to the left of the parent storm motion, though very rarely spawning tornadoes, spawn anticyclonic tornadoes. There is an increased incidence of anticyclonic tornadoes associated with tropical cyclones, and mesovortices within bow echoes may spawn anticyclonic tornadoes.[3]

The first anticyclonic tornado associated with a mesoanticyclone was spotted on WSR-88D weather radar in Sunnyvale, California on May 4, 1998. The tornado was an F2 on the Fujita Scale.[4]

Known "anticyclonic tornado" events[edit]

Date F#/EF# Rating Location Notes and References
8 June 1951 F3 Corn, Oklahoma First known tornado filmed in the US, a companion or cyclic tornado to another significant tornado. It is officially listed as one tornado event by the CDNS report and the NCDC.[5][6]
6 June 1975 F1 Freedom, Oklahoma One of three tornadoes to touch down in the area.[7][8][9]
13 June 1976 F3 Jordan, Iowa Tornadoes of 1976#June 13 – A satellite tornado to the F5 Jordan, Iowa tornado.[10][11]
3 June 1980 F1 Grand Island, Nebraska 1980 Grand Island tornado outbreak – First of three anticyclonic tornadoes in the area that night.[12][13]
3 June 1980 F3 Grand Island, Nebraska 1980 Grand Island tornado outbreak – Second of three anticyclonic tornadoes in the area that night.[12][14]
3 June 1980 F1 Grand Island, Nebraska 1980 Grand Island tornado outbreak – Last of three anticyclonic tornadoes in the area that night.[12][15]
4 April 1981 F4 West Bend, Wisconsin 1981 West Bend tornado – Strongest anticyclonic tornado ever recorded.[16]
13 June 1998 F2 North Oklahoma City, Oklahoma Tornado outbreak of June 13, 1998 – Sixth of seven tornadoes to touch down from the same supercell.[17][18]
19 April 2002 F0 Lubbock, Texas "The tornado was produced by an antimesocyclone, which was located on the north flank of a left-split storm."[19]
6 September 2004 F? Chek-Lap-Kok International Airport, Hong Kong Described as a marginal tornado.[20]
24 April 2006 F1 El Reno, Oklahoma Second of two F1 tornadoes in the area.[21][2]
20 June 2006 F1 Rushville, Nebraska A house, sheds, and outbuildings were destroyed on a farmstead.[22]
2 October 2007 EF0 Bussey, Iowa Tornadoes of 2007#October 2 – This brief anticyclonic touched down in an open field southeast of Bussey, doing no damage.[23]
10 May 2010 EF0 Nardin, Oklahoma Tornado outbreak of May 10–13, 2010 – First of five anticyclonic on this day.[24][25]
10 May 2010 EF1 Bray, Oklahoma Tornado outbreak of May 10–13, 2010 – Second of five anticyclonic tornadoes on this day; was very large at times.[24][26]
10 May 2010 EF1 Southern Norman, Oklahoma Tornado outbreak of May 10–13, 2010 – Third of five anticyclonic tornadoes on this day; it was likely a satellite tornado to the Norman–Little Axe, Oklahoma EF4 tornado.[24][27]
10 May 2010 EF1 Wayne, Oklahoma Tornado outbreak of May 10–13, 2010 – Fourth of five anticyclonic tornadoes on this day; was up to a 12 mi (0.80 km) wide and was briefly accompanied by a cyclonic EF0 satellite tornado.[24][28]
10 May 2010 EF1 Lake Eufaula, Oklahoma Tornado outbreak of May 10–13, 2010 – Last of five anticyclonic tornadoes on this day; was up to a 58 mi (1.0 km) wide.[24][29]
31 May 2013 EF2 Yukon, Oklahoma Tornado outbreak of May 26–31, 2013 – A long-lived strong satellite tornado that was southeast of the record-breaking EF3 El Reno tornado.[30][31]
4 June 2015 EF0 Simla, Colorado Tornadoes of 2015#June 4 – A brief anticyclonic tornado caused no damage.[32][33]
4 June 2015 EF0 Kutch, Colorado Tornadoes of 2015#June 4 – A brief anticyclonic tornado caused no damage.[32][34]
31 March 2016 EF0 Hohenwald, Tennessee Tornadoes of 2016#March 30–April 1 – A brief anticyclonic tornado snapped and uprooted trees, downed several large tree branches and inflicted minor roof damage to a home and barn.[35][36]
5 April 2017 EF1 Shelbyville, Tennessee Tornadoes of 2017#April 4–6 – A landspout anticyclonic tornado snapped damaged trees, cars, and structures.[37][38]
15 June 2019 EF0 Johnsonville, South Dakota Tornadoes of 2019#June 15–16 – This tornado lasted approximately 45 seconds and damaged about seven trees.[39][40][41][42]
13 March 2021 EF1 Canyon, Texas Tornadoes of 2021#March 13 — A satellite tornado snapped power poles along Interstate 27.[43]
29 July 2021 EF0 Bustleton, Philadelphia, Pennsylvania Tornado outbreak of July 28–29, 2021 – A weak tornado damaged buildings and trees.[44]
27 August 2021 EF0 Dougherty, Iowa "This very brief track was found in Sentinel satellite imagery and stayed in fields for its existence. Based on the location in the supercell, inflow wind trajectories along the left side of the track, and striation patterns in the fields, there is a high likelihood that this was an anti-cyclonic tornado."[45]
30 April 2024 EF1 Loveland, Oklahoma "An anti-cyclonic tornado damaged some trees. Preliminary information."[46]

See also[edit]

References[edit]

  1. ^ Edwards, Roger. "The Online Tornado FAQ". NWS Storm Prediction Center. Retrieved 2019-05-02.
  2. ^ a b Samenow, Jason (5 June 2013). "The rare "anticyclonic" tornado in El Reno, Okla.; not its first encounter". The Washington Post. Retrieved 9 April 2019.
  3. ^ Stull, Roland B. (2000). Meteorology for Scientists and Engineers (2nd ed.). Thomson Learning. ISBN 9780534372149.
  4. ^ Monteverdi, John P.; Blier, Warren; Stumpf, Greg; Pi, Wilfred; Anderson, Karl (November 2001). "First WSR-88D Documentation of an Anticyclonic Supercell with Anticyclonic Tornadoes: The Sunnyvale–Los Altos, California, Tornadoes of 4 May 1998". Monthly Weather Review. 129 (11): 2805–2814. Bibcode:2001MWRv..129.2805M. doi:10.1175/1520-0493(2001)129<2805:FWDOAA>2.0.CO;2. S2CID 35163346.
  5. ^ "Oklahoma Event Report: F3 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  6. ^ Grazulis, Thomas (2003). The Tornado Natures Ultimate Windstorm. Norman, OK: University of Oklahoma Press. p. 237. ISBN 9780806135380. Retrieved 2 June 2020.
  7. ^ "Oklahoma Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022."Oklahoma Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022."Oklahoma Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  8. ^ "Freedom, Oklahoma Anticyclonic Tornado - June 6, 1975". Youtube. cyclonejimcom. Archived from the original on 2021-12-21. Retrieved 9 April 2019.
  9. ^ Grazulis, Thomas P. "Twister: Fury on the Plains (1995)". imdb. Music Video Productions (co-production); The Tornado Project. Retrieved 9 April 2019.
  10. ^ "Iowa Event Report: F3 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  11. ^ Brown, John M.; Knupp, Kevin R. (October 1980). "The Iowa Cyclonic-Anticyclonic Tornado Pair and Its Parent Thunderstorm". Monthly Weather Review. 108 (10): 1626–1646. Bibcode:1980MWRv..108.1626B. doi:10.1175/1520-0493(1980)108<1626:TICATP>2.0.CO;2.
  12. ^ a b c "NWS Hastings: June 3, 1980 Grand Island Tornadoes". NWS. Retrieved April 18, 2019.
  13. ^ "Nebraska Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  14. ^ "Nebraska Event Report: F3 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022."Nebraska Event Report: F3 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  15. ^ "Nebraska Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022."Nebraska Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  16. ^ "Wisconsin Event Report: F4 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  17. ^ "Oklahoma Event Report: F2 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  18. ^ Morgan, Mike (13 June 2020). "June 13, 1998: Rare OKC twister defies nature, spins clockwise". Oklahomas News 4. KFOR. Retrieved 15 June 2020.
  19. ^ "Texas Event Report: F0 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  20. ^ Kosiba, Karen A.; Robinson, Paul; Chan, P. W.; Wurman, Joshua (2014). "Wind Field of a Nonmesocyclone Anticyclonic Tornado Crossing the Hong Kong International Airport". Advances in Meteorology. 2014 (597378). Hindawi: 1–7. doi:10.1155/2014/597378.
  21. ^ "Oklahoma Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  22. ^ "Nebraska Event Report: F1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  23. ^ "Iowa Event Report: EF0 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 10 June 2022.
  24. ^ a b c d e "The May 10, 2010 Tornado Outbreak in Oklahoma". National Weather Service Forecast Office - Norman, Oklahoma. 2010. Retrieved 2019-05-02.
  25. ^ "Oklahoma Event Report: EF0 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  26. ^ "Oklahoma Event Report: EF1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022."Oklahoma Event Report: EF1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  27. ^ "Oklahoma Event Report: EF1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  28. ^ "Oklahoma Event Report: EF1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  29. ^ "Oklahoma Event Report: EF1 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  30. ^ "Oklahoma Event Report: EF2 Tornado". National Centers for Environmental Information. National Weather Service. Retrieved 25 May 2022.
  31. ^ Norman, N. W. S. (2013-06-04). "The tornado count for May 31 will rise as analysis continues, including an anticyclonic EF2 tornado SE of the El Reno tornado. #okwx". @NWSNorman. Retrieved 2019-09-24.
  32. ^ a b "Storm Damage Surveys for June 4th Tornadoes". Denver/Boulder, CO Weather Forecast Office. Retrieved 10 April 2019.
  33. ^ Colorado Event Report: EF0 Tornado (Report). National Climatic Data Center. 2015. Retrieved November 3, 2015. {{cite report}}: Unknown parameter |agency= ignored (help)
  34. ^ Colorado Event Report: EF0 Tornado (Report). National Climatic Data Center. 2015. Retrieved November 3, 2015. {{cite report}}: Unknown parameter |agency= ignored (help)
  35. ^ Tennessee Event Report: EF0 Tornado (Report). National Centers for Environmental Information. 2016. Retrieved November 30, 2016. {{cite report}}: Unknown parameter |agency= ignored (help)
  36. ^ "March 31, 2016 Tornadoes". National Weather Service.
  37. ^ Edwards, Christina (7 April 2017). "A "very unique event": Rare anticyclonic tornado touched down in southeastern Tennessee Wednesday". WHNT News (Channel 9 FOX). Retrieved 10 April 2019.
  38. ^ Tennessee Event Report: EF0 Tornado (Report). National Centers for Environmental Information. 2017. Retrieved November 2, 2017. {{cite report}}: Unknown parameter |agency= ignored (help)
  39. ^ South Dakota Event Report: EF0 Tornado (Report). National Centers for Environmental Information. 2019. Retrieved January 12, 2020. {{cite report}}: Unknown parameter |agency= ignored (help)
  40. ^ Donegan, Brian. "A Rare Clockwise-Rotating Tornado Touched Down in South Dakota Last Weekend". Weather.com. Retrieved 19 June 2019.
  41. ^ Bates, Becky (19 June 2019). "Rare clockwise-spinning tornado touches down in South Dakota". KTVQ. Retrieved 19 June 2019.
  42. ^ Smith, Grant. "Rare anticyclonic tornado spotted in Deuel County". KELO. Retrieved 19 June 2019.
  43. ^ "Storm Events Database". National Centers for Environmental Information. Archived from the original on April 12, 2023. Retrieved April 7, 2024.
  44. ^ Storm Events Database July 29, 2021 (Report). National Centers for Environmental Information. Retrieved November 6, 2021. {{cite report}}: Unknown parameter |agency= ignored (help)
  45. ^ Storm Events Database August 27, 2021 (Report). National Centers for Environmental Information. Retrieved November 20, 2021. {{cite report}}: Unknown parameter |agency= ignored (help)
  46. ^ "NWS Damage Survey for 04/30/24 Tornado Event - Update #2" (Public Information Statement). Norman, Oklahoma: National Weather Service Norman, Oklahoma. May 2, 2024. Retrieved May 2, 2024 – via Iowa Environmental Mesonet.

External links[edit]