Tornado Intensity Estimation: Past, Present, and Future

Roger Edwards NWS Storm Prediction Center, Norman, Oklahoma

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James G. LaDue NWS Warning Decision Training Branch, Norman, Oklahoma

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John T. Ferree NWS Office of Climate, Water, and Weather Services, Norman, Oklahoma

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Kevin Scharfenberg NWS Office of Climate, Water, and Weather Services, Silver Spring, Maryland

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Chris Maier NWS Office of Climate, Water, and Weather Services, Silver Spring, Maryland

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William L. Coulbourne Applied Technology Council, Rehoboth Beach, Delaware

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During the early to middle 2000s, in response to demand for more detail in wind damage surveying and recordkeeping, a team of atmospheric scientists and wind engineers developed the enhanced Fujita (EF) scale. The EF scale, codified officially into National Weather Service (NWS) use in February 2007, offers wind speed estimates for a range of degrees of damage (DoDs) across each of 28 damage indicators (DIs). In practice, this has increased precision of damage surveys for tornado and thunderstorm-wind events. Still, concerns remain about both the representativeness of DoDs and the sufficiency of DIs, including the following: How dependable are the wind speed ranges for certain DoDs? What other DIs can be included? How can recent advances in mapping and documentation tools be integrated into the surveying process and the storm records? What changes should be made to the existing scale: why, how, and by whom? What alternative methods may be included or adapted for estimating tornado intensity?

To begin coordinated discussion on these and related topics, interested scientists and engineers (including some involved in EF scale development) organized a national EF Scale Stakeholders' Meeting, held on 2–3 March 2010 in Norman, Oklahoma. This article presents more detailed background information, summarizes the meeting, presents possibilities for the future of the EF scale and damage surveys, and solicits ideas from the engineering and atmospheric science communities.

CORRESPONDING AUTHOR: Roger Edwards, Storm Prediction Center, 120 Boren Blvd., Norman, OK 73072, E-mail: roger.edwards@noaa.gov

During the early to middle 2000s, in response to demand for more detail in wind damage surveying and recordkeeping, a team of atmospheric scientists and wind engineers developed the enhanced Fujita (EF) scale. The EF scale, codified officially into National Weather Service (NWS) use in February 2007, offers wind speed estimates for a range of degrees of damage (DoDs) across each of 28 damage indicators (DIs). In practice, this has increased precision of damage surveys for tornado and thunderstorm-wind events. Still, concerns remain about both the representativeness of DoDs and the sufficiency of DIs, including the following: How dependable are the wind speed ranges for certain DoDs? What other DIs can be included? How can recent advances in mapping and documentation tools be integrated into the surveying process and the storm records? What changes should be made to the existing scale: why, how, and by whom? What alternative methods may be included or adapted for estimating tornado intensity?

To begin coordinated discussion on these and related topics, interested scientists and engineers (including some involved in EF scale development) organized a national EF Scale Stakeholders' Meeting, held on 2–3 March 2010 in Norman, Oklahoma. This article presents more detailed background information, summarizes the meeting, presents possibilities for the future of the EF scale and damage surveys, and solicits ideas from the engineering and atmospheric science communities.

CORRESPONDING AUTHOR: Roger Edwards, Storm Prediction Center, 120 Boren Blvd., Norman, OK 73072, E-mail: roger.edwards@noaa.gov
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  • Abbey, R. F., Jr., 1976: Risk probabilities associated with tornado windspeeds. Proc. Symp. on Tornadoes: Assessment of Knowledge and Implications for Man, Lubbock, TX, Texas Tech University, 177236.

    • Search Google Scholar
    • Export Citation
  • Abbey, R. F., and T. T. Fujita, 1979: The DAPPLE method for computing tornado hazard probabilities: Refinements and theoretical considerations. Preprints, 11th Conf. on Severe Local Storms, Kansas City, MO, Amer. Meteor. Soc., 241248.

    • Search Google Scholar
    • Export Citation
  • Alexander, C. W., and J. Wurman, 2008: Updated mobile radar climatology of supercell tornado structures and dynamics. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., 19.4. [Available online at http://ams.confex.com/ams/pdfpapers/141821.pdf.]

    • Search Google Scholar
    • Export Citation
  • Beck, V., and N. Dotzek, 2010: Reconstruction of near-surface tornado wind fields from forest damage. J. Appl. Meteor. Climatol., 49, 15171537.

    • Search Google Scholar
    • Export Citation
  • Blair, S. F., D. R. Deroche, and A. E. Pietrycha, 2008: In situ observations of the 21 April 2007 Tulia, Texas tornado. Electron. J. Severe Storms Meteor., 3(3), 127.

    • Search Google Scholar
    • Export Citation
  • Brown, T. M., 2010: Development of a statistical relationship between ground-based and remotely-sensed damage in wind storms. Ph.D. dissertation, Texas Tech University, 451 pp.

    • Search Google Scholar
    • Export Citation
  • Camp, P. J., 2008: Integrating a geographical information system into storm assessment: The southeast Alabama tornado outbreak of 1 March 2007. Preprints, 24th Conf. on IIPS, New Orleans, LA, Amer. Meteor. Soc., P1.4. [Available online at http://ams.confex.com/ams/pdfpapers/134401.pdf.]

    • Search Google Scholar
    • Export Citation
  • Camp, P. J., K. Stellman, and J. Settelmaier, 2010: Utilizing mobile devices for enhanced storm damage surveys. Preprints, 26th Conf. on IIPS, Atlanta, GA, Amer. Meteor. Soc., 5B.4. [Available online at https://ams.confex.com/ams/90annual/techprogram/paper_161540.htm.]

    • Search Google Scholar
    • Export Citation
  • Doswell, C. A., III, 2003: A guide to F-scale damage assessment. NOAA Rep., 101 pp. [Available online at www.wdtb.noaa.gov/courses/ef-scale/lesson2/FinalNWSF-scaleAssessmentGuide.pdf.]

    • Search Google Scholar
    • Export Citation
  • Doswell, C. A., and D. W. Burgess, 1988: On some issues of United States tornado climatology. Mon. Wea. Rev., 116, 495501.

  • Doswell, C. A., R. Edwards, R. L. Thompson, J. A. Hart, and K. C. Crosbie, 2006: A simple and flexible method for ranking severe weather events. Wea. Forecasting, 21, 939951.

    • Search Google Scholar
    • Export Citation
  • Doswell, C. A., H. E. Brooks, and N. Doztek, 2009: On the implementation of the enhanced Fujita scale in the USA. Atmos. Res., 93, 554563.

    • Search Google Scholar
    • Export Citation
  • Dotzek, N., 2009: Derivation of physically motivated wind speed scales. Atmos. Res., 93, 564574.

  • Edwards, R., 2003: Rating tornado damage: An exercise in subjectivity. Preprints, Symp. on the F-Scale and Severe-Weather Damage Assessment, Long Beach, CA, Amer. Meteor. Soc., P1.2. [Available online at http://ams.confex.com/ams/pdfpapers/55307.pdf.]

    • Search Google Scholar
    • Export Citation
  • Edwards, R., and H. E. Brooks, 2010: Possible impacts of the enhanced Fujita scale on United States tornado data. Preprints, 25th Conf. on Severe Local Storms, Denver, CO, Amer. Meteor. Soc., P8.28. [Available online at http://ams.confex.com/ams/pdfpapers/175398.pdf.]

    • Search Google Scholar
    • Export Citation
  • FEMA, 2003: Residential safe rooms: Background and research. FEMA Rep., 11 pp. [Available online at www.fema.gov/library/file;jsessionid=18EE4A86B81890FFEB231238956739E6.WorkerLibrary?type=publishedFile&file=resshelter_bkgrdr.pdf&fileid=da2b96b0-53b4-11db-8645-000bdba87d5b.]

    • Search Google Scholar
    • Export Citation
  • FEMA, 2007: Tornado damage investigation: Greensburg, Kansas. FEMA Rep. 1699DR-KS, 29 pp. [Available online at www.fema.gov/library/viewRecord.do?id=3566.]

    • Search Google Scholar
    • Export Citation
  • Feuerstein, B., N. Dotzek, and J. Grieser, 2005: Assessing a tornado climatology from global tornado intensity distributions. J. Climate, 18, 585596.

    • Search Google Scholar
    • Export Citation
  • Fiedler, B., 2009: Suction vortices and spiral breakdown in numerical simulations of tornado-like vortices. Atmos. Sci. Lett., 10, 109114.

    • Search Google Scholar
    • Export Citation
  • Fujita, T. T., 1959: A detailed analysis of the Fargo tornadoes of June 20, 1957. University of Chicago Severe Local Storms Project Tech. Rep. 5, 29 pp.

    • Search Google Scholar
    • Export Citation
  • Fujita, T. T., 1970: Lubbock tornadoes: A study of suction spots. Weatherwise, 23, 160173.

  • Fujita, T. T., 1971: Proposed characterization of tornadoes and hurricanes by area and intensity. University of Chicago SMRP Research Paper 91, 42 pp.

    • Search Google Scholar
    • Export Citation
  • Fujita, T. T., 1992: Memoirs of an Effort to Unlock Mystery of Severe Storms during the 50 Years, 1942–1992. University of Chicago Press, 298 pp.

    • Search Google Scholar
    • Export Citation
  • Fujita, T. T., 1993: Plainfield tornado of August 28, 1990. The Tornado: Its Structure, Dynamics, Prediction and Hazards. Geophys. Monogr., Vol. 79, Amer. Geophys. Union, 117.

    • Search Google Scholar
    • Export Citation
  • Fujita, T. T., and A. D. Pearson, 1973: Results of FPP classification of 1971 and 1972 tornadoes. Preprints, Eighth Conf. on Severe Local Storms, Denver, CO, Amer. Meteor. Soc., 142145.

    • Search Google Scholar
    • Export Citation
  • Glass, F. H., and M. F. Britt, 2002: The historic Missouri–Illinois high precipitation supercell of 10 April 2001. Preprints, 21st Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., P3.3.

    • Search Google Scholar
    • Export Citation
  • Grazulis, T. P., 1993a: Significant Tornadoes: 1680–1991. Environmental Films, 1326 pp.

  • Grazulis, T. P., 1993b: A 110-year perspective of significant tornadoes. The Tornado: Its Structure, Dynamics, Prediction, and Hazards, Geophys. Monogr., Vol. 79, Amer. Geophys. Union, 467474.

    • Search Google Scholar
    • Export Citation
  • Grazulis, T. P., 1997: Significant Tornadoes: Update, 1992–1995. Environmental Films, 118 pp.

  • Guyer, J. L., and M. L. Moritz, 2003: On issues of tornado damage assessment and F-scale assignment in agricultural areas. Preprints, Symp. on the F-Scale and Severe-Weather Damage Assessment, Long Beach, CA, Amer. Meteor. Soc., 4.1. [Available online at http://ams.confex.com/ams/pdfpapers/57495.pdf.]

    • Search Google Scholar
    • Export Citation
  • Karstens, C. D., T. M. Samaras, B. D. Lee, W. A. Gallus Jr., and C. A. Finley, 2010: Near-ground pressure and wind measurements in tornadoes. Mon. Wea. Rev., 138, 25702588.

    • Search Google Scholar
    • Export Citation
  • Kelly, D. L., J. T. Schaefer, R. P. McNulty, C. A. Doswell III, and R. F. Abbey Jr., 1978: An augmented tornado climatology. Mon. Wea. Rev., 106, 11721183.

    • Search Google Scholar
    • Export Citation
  • Kopp, G. A., M. J. Morrison, E. Gavanski, D. J. Henderson, and H. P. Hong, 2010: “Three Little Pigs” project: Hurricane risk mitigation by integrated wind tunnel and fullscale laboratory tests. Nat. Hazards Rev., 11, 151161.

    • Search Google Scholar
    • Export Citation
  • LaDue, J. G., and E. A. Mahoney, 2006: Implementing the new enhanced Fujita scale within the NWS. Preprints, 23rd Conf. on Severe Local Storms, St. Louis, MO, Amer. Meteor. Soc., 5.5. [Available online at http://ams.confex.com/ams/pdfpapers/115420.pdf.]

    • Search Google Scholar
    • Export Citation
  • LaDue, J. G., and K. Ortega, 2008: Experiences in using the EF-scale since its inception. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., 8B.6. [Available online at http://ams.confex.com/ams/pdfpapers/142166.pdf.]

    • Search Google Scholar
    • Export Citation
  • Landsea, C. W., and Coauthors, 2004: The Atlantic Hurricane Database Re-Analysis Project: Documentation for the 1851–1910 alterations and additions to the HURDAT database. Hurricanes and Typhoons: Past, Present and Future, R. J. Murname and K.-B. Liu, Eds., Columbia University Press, 177221.

    • Search Google Scholar
    • Export Citation
  • Lewellen, D. C., and W. S. Lewellen, 2007: Near-surface vortex intensification through corner flow collapse. J. Atmos. Sci., 64, 21952209.

    • Search Google Scholar
    • Export Citation
  • Lewellen, B. Gong, and W. S. Lewellen, 2008: Effects of finescale debris on near-surface tornado dynamics. J. Atmos. Sci., 65, 32473262.

    • Search Google Scholar
    • Export Citation
  • Lombardo, F. T., T. M. Brown, J. A. Womble, and J. G. LaDue, 2010: The future of the EF scale. Proc. Second AAWE Workshop, Marco Island, FL, American Association for Wind Engineering.

    • Search Google Scholar
    • Export Citation
  • Marshall, T. P., 2002: Tornado damage survey at Moore, Oklahoma. Wea. Forecasting, 17, 582598.

  • Marshall, T. P., D. W. McCarthy, J. G. LaDue, J. Wurman, C. Alexander, P. Robinson, and K. Kosiba, 2008: Damage survey of the Greensburg, KS tornado. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., 8B.3. [Available online at http://ams.confex.com/ams/pdfpapers/141534.pdf.]

    • Search Google Scholar
    • Export Citation
  • McDonald, J. R., and K. C. Mehta, 2002: Summary report: Fujita Scale Forum. Texas Tech University Wind Science and Engineering Center. [Available online at www.april31974.com/fujita_scale_forum.htm.]

    • Search Google Scholar
    • Export Citation
  • McDonald, J. R., and S. Mani, 2003: F-scale modification process and proposed revisions. Preprints, Symp. on the F-Scale and Severe-Weather Damage Assessment, Long Beach, CA, Amer. Meteor. Soc., 1.1. [Available online at https://ams.confex.com/ams/pdfpapers/53999.pdf.]

    • Search Google Scholar
    • Export Citation
  • Meaden, G. T., L. Kolendowicz, A. Kosa-Kiss, I. Marcinoniene, M. Sioutas, H. Tooming, and J. Tyrrell, 2007: Comparing the theoretical versions of the Beaufort scale, the T-scale and the Fujita scale. Atmos. Res., 83, 446449.

    • Search Google Scholar
    • Export Citation
  • Minor, J. E., J. R. McDonald, and K. C. Mehta, 1977: The tornado: An engineering-oriented perspective. NOAA Tech. Memo. ERL NSSL-82, 196 pp.

    • Search Google Scholar
    • Export Citation
  • NCDC, cited 2011: Storm events database. National Climatic Data Center. [Available online at www.ncdc.noaa.gov/stormevents/.]

  • NOAA, 2007: Storm data preparation. National Weather Service Instruction 10-1605, 97 pp. [Available online at www.weather.gov/directives/sym/pd01016005curr.pdf.]

    • Search Google Scholar
    • Export Citation
  • NOAA, cited 2012: The Calumet–El Reno–Piedmont–Guthrie Tornado of May 24, 2011. [Available online at www.srh.noaa.gov/oun/?n=events-20110524-tornado-b2.]

  • Ostuno, E. J., 2008: A case study in forensic meteorology: Investigating the 3 April 1956 tornadoes in southwest lower Michigan. Electron. J. Severe Storms Meteor., 3(1), 133.

    • Search Google Scholar
    • Export Citation
  • Peterson, C. J., 2003: Factors influencing treefall risk in tornadoes in natural forests. Preprints, Symp. on the F-Scale and Severe-Weather Damage Assessment,. Long Beach, CA, Amer. Meteor. Soc., 3.1. [Available online at http://ams.confex.com/ams/pdfpapers/53292.pdf.]

    • Search Google Scholar
    • Export Citation
  • Prevatt, D. O., J. W. van de Lindt, A. Graettinger, W. Coulbourne, R. Gupta, S. Pei, S. Hensen, and D. Grau, 2011: Damage study and future direction for structural design following the Tuscaloosa tornado of 2011. University of Alabama, 56 pp [Available online at www.strongtie.com/ftp/articles/tuscaloosatornadoreport2011.pdf.]

    • Search Google Scholar
    • Export Citation
  • Ramsdell, J. V., J. P. Rishel, and A. J. Buslik, 2007: Tornado climatology of the contiguous United States. Nuclear Regulatory Commission Rep. NUREG/CR- 4461, Rev. 2, 246 pp. [Available online at www.nrc.gov/reading-rm/doc-collections/nuregs/contract/cr4461/cr4461-r2.pdf.]

    • Search Google Scholar
    • Export Citation
  • Schaefer, J. T., and J. G. Galway, 1982: Population biases in the tornado climatology. Preprints, 12th Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., 5154.

    • Search Google Scholar
    • Export Citation
  • Schaefer, J. T., and R. Edwards, 1999: The SPC tornado/severe thunderstorm database. Preprints, 11th Conf. on Applied Climatology, Dallas, TX, Amer. Meteor. Soc., 603606.

    • Search Google Scholar
    • Export Citation
  • Speheger, D. A., C. A. Doswell III, and G. J. Stumpf, 2002: The tornadoes of 3 May 1999: Event verification in central Oklahoma and related issues. Wea. Forecasting, 17, 362381.

    • Search Google Scholar
    • Export Citation
  • Thorne, P. W., and R. S. Vose, 2010: Reanalysis suitable for characterizing long-term trends: Are they really achievable? Bull. Amer. Meteor. Soc., 91, 353361.

    • Search Google Scholar
    • Export Citation
  • Verbout, S. M., H. E. Brooks, L. M. Leslie, and D. M. Schultz, 2006: Evolution of the US tornado database: 1954–2003. Wea. Forecasting, 21, 8693.

    • Search Google Scholar
    • Export Citation
  • Wegener, A., 1917: Wind- und Wasserhosen in Europa (Tornadoes and Waterspouts in Europe). Verlag Friedrich Vieweg und Sohn, 301 pp.

  • Womble, J. A., 2005: Remote-sensing applications to windstorm damage assessment. Ph. D. dissertation, Texas Tech University, 348 pp.

  • WSEC, 2006: A recommendation for an enhanced Fujita scale (EF-scale). Texas Tech University Wind Science and Engineering Center Rep., 95 pp. [Available online at www.depts.ttu.edu/weweb/pubs/fscale/efscale.pdf.]

    • Search Google Scholar
    • Export Citation
  • Wurman, J., and C. R. Alexander, 2005: The 30 May 1998 Spencer, South Dakota, storm. Part II: Comparison of observed damage and radar-derived winds in the tornadoes. Mon. Wea. Rev., 133, 97119.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., P. Robinson, and Y. Richardson, 2007: Lowlevel winds in tornadoes and potential catastrophic tornado impacts in urban areas. Bull. Amer. Meteor. Soc., 88, 3146.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., K. Kosiba, and P. Robinson, 2013: In situ Doppler radar and video observations of the interior structure of a tornado and wind-damage relationship. Bull. Amer. Meteor. Soc., in press.

    • Search Google Scholar
    • Export Citation
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