Surface Analysis near and within the Tipton, Kansas, Tornado on 29 May 2008

Bruce D. Lee WindLogics, Inc., Grand Rapids, Minnesota

Search for other papers by Bruce D. Lee in
Current site
Google Scholar
PubMed
Close
,
Catherine A. Finley WindLogics, Inc., Grand Rapids, Minnesota

Search for other papers by Catherine A. Finley in
Current site
Google Scholar
PubMed
Close
, and
Timothy M. Samaras National Technical Systems, Littleton, Colorado

Search for other papers by Timothy M. Samaras in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Data collected by a mesonet within the near-tornado environment and in the Tipton tornado on 29 May 2008 provided a rare opportunity to analyze rear-flank downdraft (RFD) outflow properties closely bounding a tornado and to characterize parcel thermodynamics being ingested into a tornado from the rear-flank downdraft. Parcels moving into the tornado on its right flank had very small negative buoyancy and considerable potential buoyancy. Measurements within and very near the tornado showed similar buoyancy characteristics to the storm inflow. Analyzed surface divergence and videographic evidence indicated that the RFD outflow just to the right and wrapping in front of the tornado was supported by parcels moving out of a narrow downdraft bordering the right flank of the tornado. Surface flow field analysis showed that parcels moved out of the downdraft-associated divergence region and into the right side of, as well as in front of, the tornado. An internal RFD surge boundary was positioned roughly 0.5 km in front of the eastern edge of the analyzed divergence region and implied downdraft.

The broader RFD outflow thermodynamic characteristics were consistent with recent research with only small negative buoyancy and substantial potential buoyancy; however, convective inhibition was considerably higher than typically found in other tornadic cases. This latter characteristic was emblematic of the broader storm environment on this day. Parcels making up the RFD outflow originated from low-levels, consistent with recent findings for tornadic rear-flank downdrafts and in contrast to past historical indications for the rear-flank downdraft source region.

Corresponding author address: Dr. Bruce D. Lee, WindLogics, Inc., Itasca Technology Exchange, 201 NW 4th St., Grand Rapids, MN 55744. Email: blee@windlogics.com

Abstract

Data collected by a mesonet within the near-tornado environment and in the Tipton tornado on 29 May 2008 provided a rare opportunity to analyze rear-flank downdraft (RFD) outflow properties closely bounding a tornado and to characterize parcel thermodynamics being ingested into a tornado from the rear-flank downdraft. Parcels moving into the tornado on its right flank had very small negative buoyancy and considerable potential buoyancy. Measurements within and very near the tornado showed similar buoyancy characteristics to the storm inflow. Analyzed surface divergence and videographic evidence indicated that the RFD outflow just to the right and wrapping in front of the tornado was supported by parcels moving out of a narrow downdraft bordering the right flank of the tornado. Surface flow field analysis showed that parcels moved out of the downdraft-associated divergence region and into the right side of, as well as in front of, the tornado. An internal RFD surge boundary was positioned roughly 0.5 km in front of the eastern edge of the analyzed divergence region and implied downdraft.

The broader RFD outflow thermodynamic characteristics were consistent with recent research with only small negative buoyancy and substantial potential buoyancy; however, convective inhibition was considerably higher than typically found in other tornadic cases. This latter characteristic was emblematic of the broader storm environment on this day. Parcels making up the RFD outflow originated from low-levels, consistent with recent findings for tornadic rear-flank downdrafts and in contrast to past historical indications for the rear-flank downdraft source region.

Corresponding author address: Dr. Bruce D. Lee, WindLogics, Inc., Itasca Technology Exchange, 201 NW 4th St., Grand Rapids, MN 55744. Email: blee@windlogics.com

Save
  • 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
  • Barnes, S. L. , 1964: A technique for maximizing details in numerical weather map analysis. J. Appl. Meteor., 3 , 396409.

  • Benjamin, S. G. , and Coauthors , 2004: An hourly assimilation-forecast cycle: The RUC. Mon. Wea. Rev., 132 , 495518.

  • Bluestein, H. B. , and A. L. Pazmany , 2000: Observations of tornadoes and other convective phenomena with a mobile, 3-mm wavelength, Doppler radar: The spring 1999 field experiment. Bull. Amer. Meteor. Soc., 81 , 29392952.

    • Search Google Scholar
    • Export Citation
  • Bluestein, H. B. , and R. M. Wakimoto , 2003: Mobile radar observations of severe convective storms. Radar and Atmospheric Science: A Collection of Essays in Honor of David Atlas, Meteor. Monogr., No. 52, Amer. Meteor. Soc., 105–136.

    • Search Google Scholar
    • Export Citation
  • Bolton, D. , 1980: The computation of equivalent potential temperature. Mon. Wea. Rev., 108 , 10461053.

  • Bonner, W. D. , 1968: Climatology of the low-level jet. Mon. Wea. Rev., 96 , 833849.

  • 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.

  • Browning, K. A. , 1964: Airflow and precipitation trajectories within severe local storms which travel to the right of the winds. J. Atmos. Sci., 21 , 634639.

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

    • Search Google Scholar
    • Export Citation
  • Davies-Jones, R. P. , D. W. Burgess , and M. Foster , 1990: Test of helicity as a forecast parameter. Preprints, 16th Conf. on Severe Local Storms, Kananaskis Park, AB, Canada, Amer. Meteor. Soc., 588–592.

    • Search Google Scholar
    • Export Citation
  • Davies-Jones, R. P. , R. J. Trapp , and H. B. Bluestein , 2001: Tornadoes and tornadic storms. Severe Convective Storms, Meteor. Monogr., No. 28, Amer. Meteor. Soc., 167–221.

    • Search Google Scholar
    • Export Citation
  • Doswell III, C. A. , and E. N. Rasmussen , 1994: The effect of neglecting the virtual temperature correction on CAPE calculations. Wea. Forecasting, 9 , 625629.

    • Search Google Scholar
    • Export Citation
  • Finley, C. A. , and B. D. Lee , 2004: High resolution mobile mesonet observations of RFD surges in the June 9 Basset, Nebraska supercell during project ANSWERS 2003. Extended Abstracts, 22nd Conf. on Severe Local Storms, Hyannis, MA, Amer. Meteor. Soc., 11.3. [Available online at http://ams.confex.com/ams/11aram22sls/techprogram/paper_82005.htm].

    • Search Google Scholar
    • Export Citation
  • Finley, C. A. , and B. D. Lee , 2008: Mobile mesonet observations of an intense RFD and multiple gust fronts in the May 23 Quinter, Kansas tornadic supercell during TWISTEX 2008. Extended Abstracts, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., P3.18. [Available online at http://ams.confex.com/ams/24SLS/techprogram/paper_142133.htm].

    • Search Google Scholar
    • Export Citation
  • Glickman, T. , 2000: Glossary of Meteorology. 2nd ed. Amer. Meteor. Soc., 855 pp.

  • 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
  • Hart, J. A. , and W. Korotky , 1991: The SHARP workstation v1.50 users guide. National Weather Service, NOAA, U.S. Dept. of Commerce, 30 pp. [Available from NWS Eastern Region Headquarters, 630 Johnson Ave., Bohemia, NY 11716].

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

    • Search Google Scholar
    • Export Citation
  • Klazura, G. E. , and D. A. Imy , 1993: A description of the initial set of analysis products available from the NEXRAD WSR-88D system. Bull. Amer. Meteor. Soc., 74 , 12931312.

    • 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. , and J. Wurman , 2008: DOW observations of multiple vortex structures in several tornadoes. Extended Abstracts, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., P3.20. [Available online at http://ams.confex.com/ams/24SLS/techprogram/paper_142194.htm].

    • Search Google Scholar
    • Export Citation
  • Lee, B. D. , C. A. Finley , and P. Skinner , 2004: Thermodynamic and kinematic analysis of multiple RFD surges for the 24 June 2003 Manchester, South Dakota cyclic tornadic supercell during Project ANSWERS 2003. Extended Abstracts, 22nd Conf. on Severe Local Storms, Hyannis, MA, Amer. Meteor. Soc., P11.2. [Available online at http://ams.confex.com/ams/11aram22sls/techprogram/paper_82000.htm].

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

    • Search Google Scholar
    • Export Citation
  • Leslie, L. M. , and R. K. Smith , 1978: The effect of vertical stability on tornadogenesis. J. Atmos. Sci., 35 , 12811288.

  • Markowski, P. M. , 2002a: Mobile mesonet observations on 3 May 1999. Wea. Forecasting, 17 , 430444.

  • Markowski, P. M. , 2002b: Hook echoes and rear flank downdrafts: A review. Mon. Wea. Rev., 130 , 852876.

  • 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. , C. Hannon , J. Frame , E. Lancaster , A. Pietrycha , R. Edwards , and R. Thompson , 2003a: Characteristics of vertical wind profiles near supercells obtained from the Rapid Update Cycle. Wea. Forecasting, 18 , 12621272.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M. , J. M. Straka , and E. N. Rasmussen , 2003b: 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
  • Marquis, J. M. , Y. Richardson , J. Wurman , and P. Markowski , 2008a: Single- and dual-Doppler analysis of a tornadic vortex and surrounding storm-scale flow in the Crowell, Texas, supercell of 30 April 2000. Mon. Wea. Rev., 136 , 50175043.

    • Search Google Scholar
    • Export Citation
  • Marquis, J. M. , Y. Richardson , J. Wurman , P. Markowski , and D. Dowell , 2008b: Mobile radar observations of tornadic supercells with multiple rear-flank gust fronts. Preprints, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., 19.3. [Available online at ams.confex.com/ams/pdfpapers/142112.pdf].

    • Search Google Scholar
    • Export Citation
  • Moller, A. R. , C. A. Doswell , M. P. Foster , and G. R. Woodall , 1994: The operational recognition of supercell thunderstorms environments and storm structures. Wea. Forecasting, 9 , 327347.

    • Search Google Scholar
    • Export Citation
  • NCDC , 2008: Storm Data. Vol. 50, No. 5, 622 pp. [Available from National Climatic Data Center, 151 Patton Ave., Asheville, NC 28801].

    • Search Google Scholar
    • Export Citation
  • Rasmussen, E. N. , 2003: Refined supercell and tornado forecast parameters. Wea. Forecasting, 18 , 530535.

  • Rasmussen, E. N. , and D. O. Blanchard , 1998: A baseline climatology of sounding-derived supercell and tornado forecast parameters. Wea. Forecasting, 13 , 11481164.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, E. N. , J. M. Straka , R. P. Davies-Jones , C. A. Doswell III , F. H. Carr , M. D. Eilts , and D. R. MacGorman , 1994: Verifications of the Origins of Rotation in Tornadoes Experiment: VORTEX. Bull. Amer. Meteor. Soc., 75 , 9951006.

    • Search Google Scholar
    • Export Citation
  • Romine, G. S. , D. W. Burgess , and R. B. Wilhelmson , 2008: A dual-polarization-radar-based assessment of the 8 May 2003 Oklahoma City area tornadic supercell. Mon. Wea. Rev., 136 , 28492870.

    • Search Google Scholar
    • Export Citation
  • Rotunno, R. , 1993: Supercell thunderstorm modeling and theory. The Tornado: Its Structure, Dynamics, Prediction, and Hazards. Geophys. Monogr., Vol. 79, Amer. Geophys. Union, 57–74.

    • Search Google Scholar
    • Export Citation
  • Rutledge, S. A. , and P. V. Hobbs , 1984: The mesoscale and microscale structure and organization of clouds and precipitation in midlatitude cyclones. XII: A diagnostic modeling study of precipitation development in narrow cold-frontal rainbands. J. Atmos. Sci., 41 , 29492972.

    • Search Google Scholar
    • Export Citation
  • Samaras, T. M. , and J. J. Lee , 2004: Pressure measurements within a large tornado. Preprints, Eighth Symp. on Integrated Observing and Assimilation Systems for Atmosphere, Oceans, and Land Surface, Seattle, WA, Amer. Meteor. Soc., 4.9.

    • 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
  • Thompson, R. L. , R. Edwards , J. A. Hart , K. L. Elmore , and P. Markowski , 2003: Close proximity soundings within supercell environments obtained from the Rapid Update Cycle. Wea. Forecasting, 18 , 12431261.

    • Search Google Scholar
    • Export Citation
  • Weisman, M. L. , and J. B. Klemp , 1982: The dependence of numerically simulated convective storms on vertical wind shear and buoyancy. Mon. Wea. Rev., 110 , 504520.

    • Search Google Scholar
    • Export Citation
  • Weiss, C. C. , and J. L. Schroeder , 2008: The 2007 and 2008 MOBILE Experiment: Developing and testing of the TTU StickNet platforms. Extended Abstracts, 24th Conf. on Severe Local Storms, Savannah, GA, Amer. Meteor. Soc., 5.1. [Available online at ams.confex.com/ams/pdfpapers/141842.pdf].

    • Search Google Scholar
    • Export Citation
  • Wicker, L. J. , 1996: The role of near surface wind shear on low-level mesocyclone generation and tornadoes. Preprints, 18th Conf. on Severe Local Storms, San Francisco, CA, Amer. Meteor. Soc., 115–119.

    • Search Google Scholar
    • Export Citation
  • Winn, W. P. , S. J. Hunyady , and G. D. Aulich , 1999: Pressure at the ground in a large tornado. J. Geophys. Res., 104 , 2206722082.

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

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 825 205 10
PDF Downloads 508 151 13