Draft:Tornadoes by strength
Highest winds observed in a tornado
[edit]During the F5 1999 Bridge Creek–Moore tornado on May 3, 1999, in the southern Oklahoma City metro area, a Doppler on Wheels situated near the tornado measured winds of 301 ± 20 mph (484 ± 32 km/h) momentarily in a small area inside the funnel approximately 100 m (330 ft) above ground level.[1] The measured winds in this tornado have been updated to 321 miles per hour (517 km/h)[2]
On May 31, 2013, a tornado hit rural areas near El Reno, Oklahoma. The tornado was originally rated as an EF3 based on damage; however, after mobile radar data analysis was conducted, it was concluded to have been an EF5 due to a measured wind speed of greater than 296 mph (476 km/h), second only to the Bridge Creek–Moore tornado. Revised RaXPol analysis found winds of 302 ± 34 mph (486 ± 55 km/h) well above ground level and ≥291 mph (468 km/h) below 10 m (33 ft) with some subvortices moving at 175 mph (282 km/h).[3] These winds may possibly be as high or higher than the winds recorded on May 3, 1999. Despite the recorded windspeed, the El Reno tornado was later downgraded back to EF3 due to the fact that no EF5 damage was found, likely due to the lack of sufficient damage indicators in the largely-rural area west of Oklahoma City.[4][5]
During the Greenfield, Iowa EF4 on May 21, 2024, Doppler on Wheels recorded wind speeds of 263–271 mph (423–436 km/h) in a very small swath inside the funnel approximately 100–106 ft (30–32 m) above radar level as the tornado went through town. After doing some mathematical and physics-based calculations, the researchers determined those measured winds were equivalent to 309–318 mph (497–512 km/h). The calculated minimum wind threshold as stated beats both the 1999 Bridge Creek–Moore tornado and the 2013 El Reno, Oklahoma tornado for minimum possible maximum windspeed; however, the highest confirmed peak windspeeds are lower than the 1999 tornado.[6][7]
Winds were measured at 262–280 mph (422–451 km/h) using portable Doppler weather radar in the Red Rock, Oklahoma, tornado during the April 26, 1991, tornado outbreak in north-central Oklahoma. Though these winds are possibly indicative of F5 intensity, this particular tornado's path never encountered any significant structures and caused minimal damage, so it was rated F4.[8]
While never observed, these tornadoes are believed to have had winds of 300 miles per hour (480 km/h) or above, which would make them among the strongest tornadoes in history. There is a questionable analysis of the 1917 Mattoon/Charleston tornado[a] published in the Geographical Review in 1917 that stated the tornado had strong "inflowing wind, which probably exceeded 400 mph (640 km/h)".[9] A 1968 Weather Bureau review of the 1968 Hansell-Charles City tornado found intense ground scouring, and initial estimates for wind speeds reached 528 mph (850 km/h); these figures were revised down to 200–300 mph (320–480 km/h).[10]
| Accepted rating | Date | Location | Highest estimated peak winds | Highest confirmed peak winds | Method | Estimating researcher / organization | Ref |
|---|---|---|---|---|---|---|---|
| F5 | May 15, 1968 | Charles City, Iowa | 528 mph (850 km/h) | 300 mph (480 km/h) | Damage survey | ||
| F5 | May 3, 1999 | Moore, Oklahoma | 321 mph (517 km/h) | 321 mph (517 km/h)[b] | Doppler on Wheels | ||
Notes
[edit]- ^ The paper states that the storm was a single tornado; later analysis suggests it was most likely a tornado family that traveled 287 miles across Missouri and Illinois.
- ^ The exact statement, released in June 2024, from the University of Illinois’ Doppler on Wheels team regarding this wind speed is:
“Wurman et al. 2007 originally reported 302 mph in the Bridgecreek, Oklahoma, 3 May 1999 tornado. This was subsequently revised upwards in Wurman et al. 2021, to 321 mph, using improved techniques.”[2]
References
[edit]- ^ Wurman, Joshua (2007). "Doppler On Wheels". Center for Severe Weather Research. Archived from the original on 2011-07-19.
- ^ a b "Flexible Array of Radars and Mesonets (FARM) statement concerning preliminary peak wind speed determinations based on Doppler On Wheels (DOW) data obtained in the Greenfield, Iowa tornado of 21 May 2024" (PDF). Champaign–Urbana metropolitan area: University of Illinois. 23 June 2024. Archived (PDF) from the original on 24 June 2024. Retrieved 24 June 2024.
- ^ Snyder, Jeff; Bluestein, H. B. (2014). "Some Considerations for the Use of High-Resolution Mobile Radar Data in Tornado Intensity Determination". Weather Forecast. 29 (4): 799–827. Bibcode:2014WtFor..29..799S. doi:10.1175/WAF-D-14-00026.1. S2CID 122669043. Archived from the original on 2020-09-06. Retrieved 2019-06-27.
- ^ Samenow, Jason (June 4, 2013). "Deadly El Reno, Okla. tornado was widest ever measured on Earth, had nearly 300 mph winds". The Washington Post. Archived from the original on May 9, 2015. Retrieved September 17, 2017.
- ^ Wright, Celine (June 4, 2013). "Discovery Channel to air special for fallen 'Storm Chasers'". Los Angeles Times. Archived from the original on December 25, 2013. Retrieved June 5, 2013.
- ^ Wurman, Joshua; Kosiba, Karen (22 June 2024). "As the 2024 #BEST field season ends, a glimpse into the data collection during the Greenfield, IA tornado. Peak wind speeds as high as 309-318 mph were calculated in a narrow region 100-160 feet ARL. These are among the highest wind speeds ever determined using DOW data" (Post on 𝕏). 𝕏 (Formerly Twitter). University of Illinois: Doppler on Wheels. Archived from the original on 22 May 2024. Retrieved 22 June 2024.
- ^ "Flexible Array of Radars and Mesonets (FARM) statement concerning preliminary peak wind speed determinations based on Doppler On Wheels (DOW) data obtained in the Greenfield, Iowa tornado of 21 May 2024" (PDF). Illinois edu. 23 June 2024. Archived (PDF) from the original on 24 June 2024. Retrieved 23 June 2024.
- ^ Bluestein, Howard B.; J.G. Ladue; H. Stein; D. Speheger; W.P. Unruh (August 1993). "Doppler Radar Wind Spectra of Supercell Tornadoes". Monthly Weather Review. 121 (8). American Meteorological Society: 2200–22. Bibcode:1993MWRv..121.2200B. doi:10.1175/1520-0493(1993)121<2200:DRWSOS>2.0.CO;2.
- ^ J. P. Carey (August 1917). "The Central Illinois Tornado of May 26, 1917". Geographical Review. 4 (2): 122–130. Bibcode:1917GeoRv...4..122C. doi:10.2307/207291. JSTOR 207291.
- ^ US Department of Commerce, NOAA. "Photos of the May 15, 1968 Northeast Iowa Tornadoes". www.weather.gov. Retrieved 2024-08-01.