• Abrams, T., 1952: The Manual of Photogrammetry. George Banta Publishing, 876 pp.

  • 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, doi:10.1175/MWR-D-11-00285.1.

    • Search Google Scholar
    • Export Citation
  • Bannon, P. R., 2002: Theoretical foundations for models of moist convection. J. Atmos. Sci., 59, 19671982, doi:10.1175/1520-0469(2002)059<1967:TFFMOM>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Barnes, S. L., 1964: A technique for maximizing details in numerical weather map analysis. J. Appl. Meteor., 3, 396409, doi:10.1175/1520-0450(1964)003<0396:ATFMDI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Bluestein, H. B., 1983: Surface meteorological observations in severe thunderstorms. Part II: Field experiments with TOTO. J. Climate Appl. Meteor., 22, 919930, doi:10.1175/1520-0450(1983)022<0919:SMOIST>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Bluestein, H. B., 1984: Photographs of the Canyon, Texas, storm on 26 May 1978. Mon. Wea. Rev., 112, 25212523, doi:10.1175/1520-0493(1984)112<2521:POTCTS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Bluestein, H. B., 1993: Synoptic-Dynamic Meteorology in Midlatitudes. Vol. 2, Observations and Theory of Weather Systems, Oxford Press, 594 pp.

  • Davies-Jones, R. P., 1986: Tornado dynamics. Thunderstorms: A Social and Technological Documentary. 2nd ed. E. Kessler, Ed., Vol. 2, University of Oklahoma Press, 197–236.

  • 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.

  • 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., 126–221.

  • Dowell, D. C., , and A. Shapiro, 2003: Stability of an iterative dual-Doppler wind synthesis in Cartesian coordinates. J. Atmos. Oceanic Technol., 20, 15521559, doi:10.1175/1520-0426(2003)020<1552:SOAIDW>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Finley, C. A., , B. D. Lee, , C. D. Karstens, , M. Grzych, , 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. 25th Conf. on Severe Local Storms, Denver, CO, Amer. Meteor. Soc., 8A.2. [Available online at https://ams.confex.com/ams/pdfpapers/176132.pdf.]

  • French, M. M., , H. B. Bluestein, , I. PopStefanija, , C. A. Baldi, , and R. T. Bluth, 2014: Mobile, phased-array, Doppler radar observations of tornadoes at X band. Mon. Wea. Rev., 142, 1010–1036, doi:10.1175/MWR-D-13-00101.1.

    • Search Google Scholar
    • Export Citation
  • Gal-Chen, T., 1978: A method for the initialization of the anelastic equations: Implications for matching models with observations. Mon. Wea. Rev., 106, 587606, doi:10.1175/1520-0493(1978)106<0587:AMFTIO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Golden, J. H., , and D. Purcell, 1978: Airflow characteristics around the Union City tornado. Mon. Wea. Rev., 106, 2228, doi:10.1175/1520-0493(1978)106<0022:ACATUC>2.0.CO;2.

    • 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, doi:10.1175/MWR3288.1.

    • Search Google Scholar
    • Export Citation
  • Hane, C. E., , and P. S. Ray, 1985: Pressure and buoyancy fields derived from Doppler radar data in a tornadic thunderstorm. J. Atmos. Sci., 42, 1835, doi:10.1175/1520-0469(1985)042<0018:PABFDF>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Holle, R. L., 1986: Photogrammetry of thunderstorms. Thunderstorms: A Social and Technological Documentary, 2nd ed. E. Kessler, Ed., Vol. 3, University of Oklahoma, 77–98.

  • Klemp, J. B., , and R. Rotunno, 1983: A study of the tornadic region within a supercell thunderstorm. J. Atmos. Sci., 40, 359377, doi:10.1175/1520-0469(1983)040<0359:ASOTTR>2.0.CO;2.

    • 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, doi:10.1175/1520-0450(1983)022<1487:AIBOMA>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Kosiba, K., , J. Wurman, , Y. Richardson, , P. Markowski, , P. Robinson, , and J. Marquis, 2013: Genesis of the Goshen County, Wyoming, tornado on 5 June 2009 during VORTEX2. Mon. Wea. Rev., 141, 11571181, doi:10.1175/MWR-D-12-00056.1.

    • Search Google Scholar
    • Export Citation
  • 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, doi:10.1175/2010MWR3454.1.

    • Search Google Scholar
    • Export Citation
  • Lemon, L. R., , and C. A. Doswell, 1979: Severe thunderstorm evolution and mesocyclone structure as related to tornadogenesis. Mon. Wea. Rev., 107, 11841197, doi:10.1175/1520-0493(1979)107<1184:STEAMS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., 2002: Hook echoes and rear-flank downdrafts: A review. Mon. Wea. Rev., 130, 852876, doi:10.1175/1520-0493(2002)130<0852:HEARFD>2.0.CO;2.

    • 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 mesocyclone obtained from pseudo-dual-Doppler radar observations. Mon. Wea. Rev., 136, 35133535, doi:10.1175/2008MWR2315.1.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., , Y. Richardson, , M. Majcen, , J. Marquis, , and J. Wurman, 2011: Characteristics of the wind field in three nontornadic low-level mesocyclones observed by the Doppler on Wheels radars. Electron. J. Severe Storms Meteor., 6 (3). [Available online at http://www.ejssm.org/ojs/index.php/ejssm/article/viewArticle/75.]

    • Search Google Scholar
    • Export Citation
  • 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, doi:10.1175/MWR-D-11-00336.1.

    • Search Google Scholar
    • Export Citation
  • Markowski, P. M., and Coauthors, 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, doi:10.1175/MWR-D-11-00337.1.

    • 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, Texas, supercell of 30 April 2000. Mon. Wea. Rev., 136, 50175043, doi:10.1175/2008MWR2442.1.

    • Search Google Scholar
    • Export Citation
  • Marquis, J., , Y. Richardson, , P. Markowski, , D. Dowell, , J. Wurman, , K. Kosiba, , P. Robinson, , and G. Romine, 2014: An investigation of the Goshen County, Wyoming, tornadic supercell of 5 June 2009 using EnKF assimilation of mobile mesonet and radar observations collected during VORTEX2. Part I: Experiment design and verification of the EnKF analyses. Mon. Wea. Rev., 142, 530554, doi:10.1175/MWR-D-13-00007.1.

    • Search Google Scholar
    • Export Citation
  • Moller, A. R., 1978: The improved NWS storm spotters’ training program at Ft. Worth, Texas. Bull. Amer. Meteor. Soc., 59, 15741582, doi:10.1175/1520-0477(1978)059<1574:TINSST>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Okubo, K., 1970: Horizontal dispersion of floatable particles in the vicinity of velocity singularities such as convergences. Deep-Sea Res., 17, 445454, doi:10.1016/0011-7471(70)90059-8.

    • Search Google Scholar
    • Export Citation
  • 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, doi:10.1175/1520-0493(1990)118<1145:TTDAAR>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, E. N., , and J. M. Straka, 2007: Evolution of low-level angular momentum in the 2 June 1995 Dimmitt, Texas, tornado cyclone. J. Atmos. Sci., 64, 13651378, doi:10.1175/JAS3829.1.

    • Search Google Scholar
    • Export Citation
  • Ray, P. S., , C. L. Ziegler, , W. Bumgarner, , and R. J. Serafin, 1980: Single- and multiple-Doppler radar observations of tornadic storms. Mon. Wea. Rev., 108, 16071625, doi:10.1175/1520-0493(1980)108<1607:SAMDRO>2.0.CO;2.

    • 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. 26th Conf. on Severe Local Storms, Nashville, TN, Amer. Meteor. Soc., P13.3. [Available online at https://ams.confex.com/ams/26SLS/webprogram/Paper212526.html.]

  • Rotunno, R., , and J. B. Klemp, 1982: The influence of the shear-induced pressure gradient on thunderstorm motion. Mon. Wea. Rev., 110, 136151, doi:10.1175/1520-0493(1982)110<0136:TIOTSI>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Rotunno, R., , and J. B. Klemp, 1985: On the rotation and propagation of simulated supercell thunderstorms. J. Atmos. Sci., 42, 271292, doi:10.1175/1520-0469(1985)042<0271:OTRAPO>2.0.CO;2.

    • 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, doi:10.1175/1520-0426(1996)013<0921:AMMFFM>2.0.CO;2.

    • 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, doi:10.1175/2010MWR3568.1.

    • 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, doi:10.1175/MWR-D-12-00036.1.

    • 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. 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.]

  • Weiss, J., 1991: The dynamics of enstrophy transfer in two-dimensional hydrodynamics. Physica, 48, 273294.

  • Wurman, J., 2001: The DOW mobile multiple-Doppler network. 30th Int. Conf. on Radar Meteorology, Munich, Germany, Amer. Meteor. Soc., P3.3. [Available online at https://ams.confex.com/ams/30radar/techprogram/paper_21572.htm.]

  • Wurman, J., , Y. Richardson, , C. Alexander, , S. Weygandt, , and P. F. Zhang, 2007: Dual-Doppler and single-Doppler analysis of a tornadic storm undergoing mergers and repeated tornadogenesis. Mon. Wea. Rev., 135, 736758, doi:10.1175/MWR3276.1.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., , K. 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, doi:10.1175/2010MWR3330.1.

    • Search Google Scholar
    • Export Citation
  • Wurman, J., , D. Dowell, , Y. Richardson, , P. Markowski, , E. Rasmussen, , D. Burgess, , L. Wicker, , and H. B. Bluestein, 2012: The Second Verification of the Origins of Rotation in Tornadoes Experiment: VORTEX2. Bull. Amer. Meteor. Soc., 93, 11471170, doi:10.1175/BAMS-D-11-00010.1.

    • 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 the wind–damage relationship. Bull. Amer. Meteor. Soc., 94, 835846, doi:10.1175/BAMS-D-12-00114.1.

    • Search Google Scholar
    • Export Citation
  • Zehnder, J. A., , J. Hu, , and A. Razdan, 2007: A stereo photogrammetric technique applied to orographic convection. Mon. Wea. Rev., 135, 22652277, doi:10.1175/MWR3401.1.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 57 57 14
PDF Downloads 25 25 8

Observations of Wall Cloud Formation in Supercell Thunderstorms during VORTEX2

View More View Less
  • 1 Department of Atmospheric Sciences, Lyndon State College, Lyndonville, Vermont
© Get Permissions
Restricted access

Abstract

This study presents an integrated analysis of dual-Doppler, cloud photogrammetry, surface mobile mesonet, and sounding data to examine wall cloud formation in two supercells observed during the Verification of the Origins of Rotation in Tornadoes Experiment II (VORTEX2). One of the wall clouds contained significant rotation and spawned an (enhanced Fujita) EF2 tornado, while the other was clearly displaced horizontally from the mesocyclone and exhibited little rotation at the time of data collection. Backward parcel trajectories show that the majority of the air entering the wall cloud base originates in the forward-flank region. A small fraction of the parcels enter the wall cloud base from the inflow. Some rear-flank downdraft parcels descend into the strongly rotating wall cloud. For both wall clouds, much of the observed wall cloud lowering is attributed to evaporatively cooled parcels in the forward-flank region being ingested into the low-level updraft. Additional wall cloud-base lowering is observed near the circulation center of the strongly rotating wall cloud. This localized lowering is created by the pressure deficit and associated cooling. The observational results presented herein are compared to long-standing wall cloud formation conceptual models published in the refereed literature.

Corresponding author address: Nolan T. Atkins, Department of Atmospheric Sciences, Lyndon State College, 1001 College Rd., Lyndonville, VT 05851. E-mail: nolan.atkins@lyndonstate.edu

A comment/reply has been published regarding this article and can be found at http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-15-0126.1

Abstract

This study presents an integrated analysis of dual-Doppler, cloud photogrammetry, surface mobile mesonet, and sounding data to examine wall cloud formation in two supercells observed during the Verification of the Origins of Rotation in Tornadoes Experiment II (VORTEX2). One of the wall clouds contained significant rotation and spawned an (enhanced Fujita) EF2 tornado, while the other was clearly displaced horizontally from the mesocyclone and exhibited little rotation at the time of data collection. Backward parcel trajectories show that the majority of the air entering the wall cloud base originates in the forward-flank region. A small fraction of the parcels enter the wall cloud base from the inflow. Some rear-flank downdraft parcels descend into the strongly rotating wall cloud. For both wall clouds, much of the observed wall cloud lowering is attributed to evaporatively cooled parcels in the forward-flank region being ingested into the low-level updraft. Additional wall cloud-base lowering is observed near the circulation center of the strongly rotating wall cloud. This localized lowering is created by the pressure deficit and associated cooling. The observational results presented herein are compared to long-standing wall cloud formation conceptual models published in the refereed literature.

Corresponding author address: Nolan T. Atkins, Department of Atmospheric Sciences, Lyndon State College, 1001 College Rd., Lyndonville, VT 05851. E-mail: nolan.atkins@lyndonstate.edu

A comment/reply has been published regarding this article and can be found at http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-15-0126.1

Save