Genesis of the Goshen County, Wyoming, Tornado on 5 June 2009 during VORTEX2

Karen Kosiba Center for Severe Weather Research, Boulder, Colorado

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Joshua Wurman Center for Severe Weather Research, Boulder, Colorado

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Yvette Richardson Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania

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Paul Markowski Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania

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Paul Robinson Center for Severe Weather Research, Boulder, Colorado

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James Marquis Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania

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Abstract

The genesis of a strong and long-lived tornado observed during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) in Goshen County, Wyoming, on 5 June 2009 is studied. Mobile radar, mobile mesonet, rawinsonde, and photographic data are used to produce an integrated analysis of the evolution of the wind, precipitation, and thermodynamic fields in the parent supercell to deduce the processes that resulted in tornadogenesis. Several minutes prior to tornadogenesis, the rear-flank downdraft intensifies, and a secondary rear-flank downdraft forms and cyclonically wraps around the developing tornado. Kinematic and thermodynamic analyses suggest that horizontal vorticity created in the forward flank and hook echo is tilted and then stretched near the developing tornado. Tilting and stretching are enhanced in the developing low-level circulation as the secondary rear-flank downdraft develops, intensifies, and wraps around the circulation center. Shortly thereafter, the tornado forms. Tornadogenesis does not proceed steadily. Strengthening, weakening, and renewed intensification of the tornado are documented in photographic, reflectivity, Doppler velocity, and dual-Doppler fields and are associated with, and shortly follow, changes in the secondary rear-flank downdraft, convergence, location of the vortex relative to the updraft/downdraft couplet, tilting and stretching near and in the developing tornado, and the evolution of total circulation.

Corresponding author address: Dr. Karen Ann Kosiba, Center for Severe Weather Research, 1945 Vassar Circle, Boulder, CO 80305. E-mail: kakosiba@cswr.org

Abstract

The genesis of a strong and long-lived tornado observed during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) in Goshen County, Wyoming, on 5 June 2009 is studied. Mobile radar, mobile mesonet, rawinsonde, and photographic data are used to produce an integrated analysis of the evolution of the wind, precipitation, and thermodynamic fields in the parent supercell to deduce the processes that resulted in tornadogenesis. Several minutes prior to tornadogenesis, the rear-flank downdraft intensifies, and a secondary rear-flank downdraft forms and cyclonically wraps around the developing tornado. Kinematic and thermodynamic analyses suggest that horizontal vorticity created in the forward flank and hook echo is tilted and then stretched near the developing tornado. Tilting and stretching are enhanced in the developing low-level circulation as the secondary rear-flank downdraft develops, intensifies, and wraps around the circulation center. Shortly thereafter, the tornado forms. Tornadogenesis does not proceed steadily. Strengthening, weakening, and renewed intensification of the tornado are documented in photographic, reflectivity, Doppler velocity, and dual-Doppler fields and are associated with, and shortly follow, changes in the secondary rear-flank downdraft, convergence, location of the vortex relative to the updraft/downdraft couplet, tilting and stretching near and in the developing tornado, and the evolution of total circulation.

Corresponding author address: Dr. Karen Ann Kosiba, Center for Severe Weather Research, 1945 Vassar Circle, Boulder, CO 80305. E-mail: kakosiba@cswr.org
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  • Adlerman, E. J., 2003: Numerical simulations of cyclic storm behavior: Mesocyclogenesis and tornadogenesis. Ph.D. dissertation, University of Oklahoma, 217 pp. [Available from School of Meteorology, University of Oklahoma, 100 East Boyd, Suite 1310, Norman, OK 73019.]

  • Adlerman, E. J., K. K. Droegemeier, and R. Davies-Jones, 1999: A numerical simulation of cyclic mesocyclogenesis. J. Atmos. Sci., 56, 20452069.

    • Search Google Scholar
    • Export Citation
  • Alexander, C., and J. Wurman, 2005: The 30 May 1998 Spencer, South Dakota, storm. Part I: The structural evolution and environment of the supercell tornadoes. Mon. Wea. Rev., 133, 7296.

    • Search Google Scholar
    • Export Citation
  • Alexander, C., 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., 19.3. [Available online at https://ams.confex.com/ams/pdfpapers/142112.pdf.]

  • Atkins, N. T., A. McGee, R. Ducharme, R. M. Wakimoto, and J. Wurman, 2012: The LaGrange tornado during VORTEX2. Part II: Photogrammetric analysis of the tornado combined with dual-Doppler radar data. Mon. Wea. Rev., 140, 29392958.

    • Search Google Scholar
    • Export Citation
  • Barnes, S. L., 1964: A technique for maximizing details in numerical weather map analysis. J. Appl. Meteor., 3, 396409.

  • Beck, J. R., J. L. Schroeder, and J. M. Wurman, 2006: High-resolution, dual-Doppler analyses of the 29 May 2001 Kress, Texas, cyclic supercell. Mon. Wea. Rev., 134, 31253148.

    • Search Google Scholar
    • Export Citation
  • Biggerstaff, M. I., and Coauthors, 2005: The Shared Mobile Atmospheric Research and Teaching radar: A collaboration to enhance research and teaching. Bull. Amer. Meteor. Soc., 86, 12631274.

    • Search Google Scholar
    • Export Citation
  • Brandes, E. A., 1977: Gust front evolution and tornado genesis as viewed by Doppler radar. J. Appl. Meteor., 16, 333338.

  • Brandes, E. A., 1978: Mesocyclone evolution and tornadogenesis: Some observations. Mon. Wea. Rev., 106, 9951011.

  • Brandes, E. A., 1981: Finestructure of the Del City-Edmond tornadic mesocirculation. Mon. Wea. Rev., 109, 635647.

  • Brandes, E. A., 1984: Vertical vorticity generation and mesoscyclone sustenance in tornadic thunderstorms: The observational evidence. Mon. Wea. Rev., 112, 22532269.

    • Search Google Scholar
    • Export Citation
  • Byko, Z., P. Markowski, Y. Richardson, J. Wurman, and E. Adlerman, 2009: Descending reflectivity cores in supercell thunderstorms observed by mobile radars and in a high-resolution numerical simulation. Wea. Forecasting, 24, 155186.

    • Search Google Scholar
    • Export Citation
  • Davies-Jones, R., 2008: Can a descending rain curtain in a supercell instigate tornadogenesis barotropically? J. Atmos. Sci., 65, 24692497.

    • Search Google Scholar
    • Export Citation
  • Davies-Jones, R., and H. Brooks, 1993: Mesocyclogenesis from a theoretical perspective. The Tornado: Its Structure, Dynamics, Prediction, and Hazards, Geophys. Monogr., Vol. 79, Amer. Geophys. Union, 105–114.

  • Davies-Jones, R., R. J. Trapp, and H. B. Bluestein, 2001: Tornadoes and tornadic storms. Severe Convective Storms, Meteor. Monogr., No. 50, Amer. Meteor. Soc., 167–222.

  • Dowell, D. C., and H. B. Bluestein, 1997: The Arcadia, Oklahoma, storm of 17 May 1981: Analysis of a supercell during tornadogenesis. Mon. Wea. Rev., 125, 25622582.

    • Search Google Scholar
    • Export Citation
  • Dowell, D. C., and H. B. Bluestein, 2002a: The 8 June 1995 McLean, Texas, storm. Part I: Observations of cyclic tornadogenesis. Mon. Wea. Rev., 130, 26262648.

    • Search Google Scholar
    • Export Citation
  • Dowell, D. C., and H. B. Bluestein, 2002b: The 8 June 1995 McLean, Texas, storm. Part II: Cyclic tornado formation, maintenance, and dissipation. Mon. Wea. Rev., 130, 26492670.

    • Search Google Scholar
    • Export Citation
  • Finley, C. A., B. D. Lee, M. Grzych, C. D. Karstens, and T. M. Samaras, 2010: Mobile mesonet observations of the rear-flank downdraft evolution associated with a violent tornado near Bowdle, SD on 22 May 2010. Preprints, 25th Conf. on Severe Local Storms, Denver, CO, Amer. Meteor. Soc., 8A.2. [Available online at https://ams.confex.com/ams/pdfpapers/176132.pdf.]

  • Fujita, T. T., 1981: Tornadoes and downbursts in the context of generalized planetary scales. J. Atmos. Sci., 38, 15111534.

  • Fujita, T. T., and R. M. Wakimoto, 1982: Anticyclonic tornadoes in 1980 and 1981. Preprints, 12th Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., 213216.

    • Search Google Scholar
    • Export Citation
  • Grzych, M. L., B. D. Lee, and C. A. Finley, 2007: Thermodynamic analysis of supercell rear-flank downdrafts from Project ANSWERS. Mon. Wea. Rev., 135, 240246.

    • Search Google Scholar
    • Export Citation
  • Heymsfield, G. M., 1978: Kinematic and dynamic aspects of the Harrah tornadic storm analyzed from dual-Doppler radar data. Mon. Wea. Rev., 106, 233254.

    • Search Google Scholar
    • Export Citation
  • Hirth, B. D., J. L. Schroeder, and C. C. Weiss, 2008: Surface analysis of the rear-flank downdraft outflow in two tornadic supercells. Mon. Wea. Rev., 136, 23442363.

    • Search Google Scholar
    • Export Citation
  • Klemp, J. B., and R. Rotunno, 1983: A study of the tornadic region within a supercell thunderstorm. J. Atmos. Sci., 40, 359377.

  • Klemp, J. B., R. B. Wilhelmson, and P. S. Ray, 1981: Observed and numerically simulated structure of a mature supercell thunderstorm. J. Atmos. Sci., 38, 15581580.

    • Search Google Scholar
    • Export Citation
  • Koch, S. E., M. desJardins, and P. J. Kocin, 1983: An interactive Barnes objective map analysis scheme for use with satellite and conventional data. J. Climate Appl. Meteor., 22, 14871503.

    • Search Google Scholar
    • Export Citation
  • Kosiba, K. A., and J. Wurman, 2008: DOW observations of multiple vortex structure in several tornadoes. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., P3.20. [Available online at https://ams.confex.com/ams/pdfpapers/142194.pdf.]

  • Lee, B. D., C. A. Finley, and T. M. Samaras, 2011: Surface analysis near and within the Tipton, Kansas, tornado on 29 May 2008. Mon. Wea. Rev., 139, 370386.

    • Search Google Scholar
    • Export Citation
  • Lee, W.-C., and J. Wurman, 2005: The diagnosed structure of the Mulhall tornado. J. Atmos. Sci., 62, 23732393.

  • Leise, J. A., 1982: A multidimensional scale-telescoped filter and data extension package. NOAA Tech. Memo. ERL WRL-82, 19 pp. [Available from NOAA Office of Oceanic and Atmospheric Research, Silver Spring Metro Center, Bldg. 3, Room 11627, Silver Spring, MD 20910.]

  • Lemon, L. R., and C. A. Doswell, 1979: Severe thunderstorm evolution and mesocyclone structure as related to tornadogenesis. Mon. Wea. Rev., 107, 11841197.

    • Search Google Scholar
    • Export Citation
  • Majcen, M., P. Markowski, Y. Richardson, D. Dowell, and J. Wurman, 2008: Multipass objective analyses of Doppler radar data. J. Atmos. Oceanic Technol., 25, 18451858.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., 2002: Hook echoes and rear-flank downdrafts: A review. Mon. Wea. Rev., 130, 852876.

  • Markowski, P. M., and Y. P. Richardson, 2009: Tornadogenesis: Our current understanding, forecasting considerations, and questions to guide future research. Atmos. Res., 93, 310.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., J. M. Straka, and E. N. Rasmussen, 2002: Direct surface thermodynamic observations within the rear-flank downdrafts of nontornadic and tornadic supercells. Mon. Wea. Rev., 130, 16921721.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., J. M. Straka, and E. N. Rasmussen, 2003: Tornadogenesis resulting from the transport of circulation by a downdraft: Idealized numerical simulations. J. Atmos. Sci., 60, 795823.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., E. Rasmussen, J. Straka, R. Davies-Jones, Y. Richardson, and R. J. Trapp, 2008: Vortex lines within low-level mesocyclones obtained from pseudo-dual-Doppler radar observations. Mon. Wea. Rev., 136, 35133535.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., M. Majcen, Y. Richardson, J. Marquis, and J. Wurman, 2011: Characteristics of the wind field in a trio of nontornadic low-level mesocyclones observed by the Doppler on Wheels radars. Electron. J. Severe Storms Meteor.,5 (7). [Available online at http://www.ejssm.org/ojs/index.php/ejssm/article/view/75/63.]

  • Markowski, P. M., and Coauthors, 2012a: The pretornadic phase of the Goshen County, Wyoming, supercell of 5 June 2009 intercepted by VORTEX2. Part I: Evolution of kinematic and surface thermodynamic fields. Mon. Wea. Rev., 140, 28872915.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., Y. Richardson, J. Marquis, R. Davies-Jones, J. Wurman, K. Kosiba, P. Robinson, and E. Rasmussen, 2012b: The pretornadic phase of the Goshen County, Wyoming, supercell of 5 June 2009 intercepted by VORTEX2. Part II: Intensification of low-level rotation. Mon. Wea. Rev., 140, 29162938.

    • Search Google Scholar
    • Export Citation
  • Marquis, J., Y. Richardson, J. Wurman, and P. Markowski, 2008: Single- and dual-Doppler analysis of a tornadic vortex and surrounding storm scale flow in the Crowell, TX, supercell of 30 April 2000. Mon. Wea. Rev., 136, 50175043.

    • Search Google Scholar
    • Export Citation
  • Marquis, J., Y. Richardson, P. Markowski, D. Dowell, and J. Wurman, 2012a: Tornado maintenance investigated with high-resolution dual-Doppler and EnKF analysis. Mon. Wea. Rev., 140, 327.

    • Search Google Scholar
    • Export Citation
  • Marquis, J., Y. Richardson, P. Markowski, D. Dowell, J. Wurman, K. Kosiba, and P. Robinson, 2012b: An investigation of the tornadic stage of the Goshen County, Wyoming, supercell of 5 June 2009 using EnKF assimilation of mobile radar data collected during VORTEX2. Preprints, 26th Conf. on Severe Local Storms, Nashville, TN, Amer. Meteor. Soc., 169. [Available online at https://ams.confex.com/ams/26SLS/webprogram/Paper211344.html]

  • Parker, M. D., 2012: Impacts of lapse rates upon low-level rotation in idealized storms. J. Atmos. Sci., 69, 538559.

  • Pauley, P. M., and X. Wu, 1990: The theoretical, discrete, and actual response of the Barnes objective analysis scheme for one- and two-dimensional fields. Mon. Wea. Rev., 118, 11451163.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, E. N., M. S. Gilmore, and R. Davies-Jones, 2006: A preliminary survey of rear-flank descending reflectivity cores in supercell storms. Wea. Forecasting, 21, 923928.

    • Search Google Scholar
    • Export Citation
  • Ray, P. S., 1976: Vorticity and divergence fields within tornadic storms from dual-Doppler observations. J. Appl. Meteor., 15, 879890.

    • Search Google Scholar
    • Export Citation
  • Ray, P. S., R. J. Doviak, G. B. Walker, D. Sirmans, J. Carter, and B. Bumgarner, 1975: Dual-Doppler observation of a tornadic storm. J. Appl. Meteor., 14, 15211530.

    • Search Google Scholar
    • Export Citation
  • Ray, P. S., B. C. Johnson, K. W. Johnson, J. S. Bradberry, J. J. Stephens, K. K. Wagner, R. B. Wilhelmson, and J. B. Klemp, 1981: The morphology of several tornadic storms on 20 May 1977. J. Atmos. Sci., 38, 16431663.

    • Search Google Scholar
    • Export Citation
  • Richardson, Y. P., P. Markowski, J. N. Marquis, J. Wurman, K. A. Kosiba, P. Robinson, D. W. Burgess, and C. C. Weiss, 2012: Tornado maintenance and demise in the Goshen County, Wyoming supercell of 5 June 2009 intercepted by VORTEX2. Preprints, 26th Conf. on Severe Local Storms, Nashville, TN, Amer. Meteor. Soc., 13.3. [Available online at https://ams.confex.com/ams/26SLS/webprogram/Paper212526.html]

  • Rotunno, R., and J. B. Klemp, 1985: On the rotation and propagation of simulated supercell thunderstorms. J. Atmos. Sci., 42, 271292.

    • Search Google Scholar
    • Export Citation
  • Straka, J. M., E. N. Rasmussen, and S. E. Fredrickson, 1996: A mobile mesonet for finescale meteorological observations. J. Atmos. Oceanic Technol., 13, 921936.

    • Search Google Scholar
    • Export Citation
  • Straka, J. M., E. N. Rasmussen, R. P. Davies-Jones, and P. M. Markowski, 2007: An observational and idealized numerical examination of low-level counter-rotating vortices toward the rear flank of supercells. Electron. J. Severe Storms Meteor.,2 (8). [Available online at http://www.ejssm.org/ojs/index.php/ejssm/article/view/32/33.]

  • Trapp, R. J., 1999: Observations of nontornadic low-level mesocyclones and attendant tornadogenesis failure during VORTEX. Mon. Wea. Rev., 127, 16931705.

    • Search Google Scholar
    • Export Citation
  • Wakimoto, R. M., and H. Cai, 2000: Analysis of a nontornadic storm during VORTEX 95. Mon. Wea. Rev., 128, 565592.

  • Wakimoto, R. M., C.-H. Liu, and H. Cai, 1998: The Garden City, Kansas, storm during VORTEX 95. Part I: Overview of the storm’s life cycle and mesocyclogenesis. Mon. Wea. Rev., 126, 372392.

    • Search Google Scholar
    • Export Citation
  • Wakimoto, R. M., N. T. Atkins, and J. Wurman, 2011: The LaGrange tornado during VORTEX2. Part I: Photogrammetric analysis of the tornado combined with single-Doppler radar data. Mon. Wea. Rev., 139, 22332258.

    • Search Google Scholar
    • Export Citation
  • Wakimoto, R. M., P. Stauffer, W.-C. Lee, N. T. Atkins, and J. Wurman, 2012: Finescale structure of the LaGrange, Wyoming, tornado during VORTEX2: GBVTD and photogrammetric analyses. Mon. Wea. Rev., 140, 33973418.

    • Search Google Scholar
    • Export Citation
  • Waugh, S., and S. E. Fredrickson, 2010: An improved aspirated temperature system for mobile meteorological observations, especially in severe weather. Preprints, 25th Conf. on Severe Local Storms, Denver, CO, Amer. Meteor. Soc., P5.2. [Available online at https://ams.confex.com/ams/25SLS/webprogram/Paper176205.html]

  • Wicker, L. J., and R. B. Wilhelmson, 1995: Simulation and analysis of tornado development and decay within a three-dimensional supercell thunderstorm. J. Atmos. Sci., 52, 26752703.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., 2001: The DOW mobile multiple-Doppler network. Preprints, 30th Int. Conf. on Radar Meteorology, Munich, Germany, Amer. Meteor. Soc., P3.3. [Available online at https://ams.confex.com/ams/pdfpapers/21572.pdf.]

  • Wurman, J., 2002: The multiple vortex structure of a tornado. Wea. Forecasting, 17, 473505.

  • Wurman, J., and S. Gill, 2000: Fine-scale radar observations of the Dimmitt, Texas, tornado. Mon. Wea. Rev., 128, 21352164.

  • Wurman, J., and M. Randall, 2001: An inexpensive, mobile, rapid-scan radar. Preprints, 30th Conf. on Radar Meteorology, Munich, Germany, Amer. Meteor. Soc., P3.4. [Available online at https://ams.confex.com/ams/pdfpapers/21577.pdf]

  • Wurman, J., J. Straka, and E. Rasmussen, 1996a: Fine-scale Doppler radar observation of tornadoes. Science, 272, 17741777.

  • Wurman, J., J. Straka, and E. Rasmussen, 1996b: Preliminary radar observations of the structure of tornadoes. Preprints, 18th Conf. on Severe Local Storms, San Francisco, CA, Amer. Meteor. Soc., 17–22.

  • Wurman, J., J. Straka, E. Rasmussen, M. Randall, and A. Zahrai, 1997: Design and deployment of a portable, pencil-beam, pulsed, 3-cm Doppler radar. J. Atmos. Oceanic Technol., 14, 15021512.

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

    • Search Google Scholar
    • Export Citation
  • Wurman, J., Y. Richardson, C. Alexander, S. Weygandt, and P. F. Zhang, 2007b: Dual-Doppler and single-Doppler analysis of a tornadic storm undergoing mergers and repeated tornadogenesis. Mon. Wea. Rev., 135, 736758.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., Y. Richardson, C. Alexander, S. Weygandt, and P. F. Zhang, 2007c: Dual-Doppler analysis of winds and vorticity budget terms near a tornado. Mon. Wea. Rev., 135, 23922405.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., P. Robinson, W. Lee, C. R. Alexander, and K. A. Kosiba, 2008: Rapid-scan mobile radar 3D GBVTD and traditional analysis of tornadogenesis. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., P13.6. [Available online at https://ams.confex.com/ams/pdfpapers/142176.pdf.]

  • Wurman, J., K. A. Kosiba, P. Markowski, Y. Richardson, D. Dowell, and P. Robinson, 2010: Finescale single- and dual-Doppler analysis of tornado intensification, maintenance, and dissipation in the Orleans, Nebraska, supercell. Mon. Wea. Rev., 138, 44394455.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., D. Dowell, Y. Richardson, P. Markowski, E. Rasmussen, D. Burgess, L. Wicker, and H. Bluestein, 2012: The second Verification of the Origins of Rotation in Tornadoes Experiment: VORTEX2. Bull. Amer. Meteor. Soc., 93, 11471170.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., K. A. 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.

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