TY - JOUR
T1 - In situ and radar observations of the low reflectivity ribbon in supercells during VORTEX2
AU - Griffin, Casey B.
AU - Weiss, Christopher C.
AU - Reinhart, Anthony E.
AU - Snyder, Jeffrey C.
AU - Bluestein, Howard B.
AU - Wurman, Joshua
AU - Kosiba, Karen A.
N1 - Funding Information:
Acknowledgments. This work was supported by National Science Foundation (NSF) Grants AGS-0800542, AGS-0948492, AGS-0964088, AGS-1262048, and AGS-1447268. Casey B. Griffin was supported in part by the AMS 21st Century Campaign’s graduate fellowship. Funding for Jeffrey Snyder was provided by NOAA/Office of Oceanic and Atmospheric Research under NOAA–University of Oklahoma Cooperative Agreement NA11OAR4320072, U.S. Department of Commerce. The DOW facility is supported by NSF Grants AGS-0734001 and AGS-1361237. VORTEX2 logistics were supported by NSF Grant AGS-0724318. The authors thank Eric Bruning and Johannes Dahl for their help in improving this work as a part of the lead author’s master’s thesis at TTU. The authors also thank Zach Weinhoff for scientific conversation. We thank the students and faculty from the TTU Atmospheric Science Group; the TTU National Wind Institute; the University of Michigan Atmospheric, Oceanic, and Space Science program; the University of Oklahoma (UMass X-Pol); and the Center for Severe Weather Research (DOWs) for their dedicated efforts in the field. Finally, the authors thank the three anonymous reviewers whose suggestions greatly improved this work.
Funding Information:
This work was supported by National Science Foundation (NSF) Grants AGS-0800542, AGS-0948492, AGS-0964088, AGS-1262048, and AGS-1447268. Casey B. Griffin was supported in part by the AMS 21st Century Campaign's graduate fellowship. Funding for Jeffrey Snyder was provided by NOAA/Office of Oceanic and Atmospheric Research under NOAA-University of Oklahoma Cooperative Agreement NA11OAR4320072, U.S. Department of Commerce. The DOW facility is supported by NSF Grants AGS-0734001 and AGS-1361237. VORTEX2 logistics were supported by NSF Grant AGS-0724318. The authors thank Eric Bruning and Johannes Dahl for their help in improving this work as a part of the lead author's master's thesis at TTU. The authors also thank Zach Weinhoff for scientific conversation. We thank the students and faculty from the TTU Atmospheric Science Group; the TTU National Wind Institute; the University of Michigan Atmospheric, Oceanic, and Space Science program; the University of Oklahoma (UMass X-Pol); and the Center for Severe Weather Research (DOWs) for their dedicated efforts in the field. Finally, the authors thank the three anonymous reviewers whose suggestions greatly improved this work.
Publisher Copyright:
© 2018 American Meteorological Society.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - During the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) field campaign, mobile radars observed a previously undocumented feature: the low-reflectivity ribbon (LRR). The LRR was characterized by reduced reflectivity ZH and differential reflectivity ZDR through a narrow region extending from the intersection of the hook and forward-flank regions of supercells. This study synthesizes kinematic and polarimetric radar observations with in situ measurements taken by the "StickNet" observing network. StickNet data have been used to establish that the LRR is associated with a localized minimum in pseudoequivalent potential temperature θep Pronounced drops in θep are observed by nine separate probes in three different supercell thunderstorms. Both single- and dual-Doppler analyses are used to examine the two- and three-dimensional structures of the winds within the LRR, revealing that the LRR is associated with cyclonic vertical vorticity aloft. Polarimetric radar observations are used to study the hydrometeor characteristics and the processes that cause those hydrometers to be present. Special consideration is given to the analysis of the vertical distribution of traditional and polarimetric variables, as well as the evolution of the kinematic fields retrieved by dual-Doppler analysis. The combination of thermodynamic, kinematic, and inferred microphysical observations supports a hypothesis that the LRR comprises sparse, large hail.
AB - During the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) field campaign, mobile radars observed a previously undocumented feature: the low-reflectivity ribbon (LRR). The LRR was characterized by reduced reflectivity ZH and differential reflectivity ZDR through a narrow region extending from the intersection of the hook and forward-flank regions of supercells. This study synthesizes kinematic and polarimetric radar observations with in situ measurements taken by the "StickNet" observing network. StickNet data have been used to establish that the LRR is associated with a localized minimum in pseudoequivalent potential temperature θep Pronounced drops in θep are observed by nine separate probes in three different supercell thunderstorms. Both single- and dual-Doppler analyses are used to examine the two- and three-dimensional structures of the winds within the LRR, revealing that the LRR is associated with cyclonic vertical vorticity aloft. Polarimetric radar observations are used to study the hydrometeor characteristics and the processes that cause those hydrometers to be present. Special consideration is given to the analysis of the vertical distribution of traditional and polarimetric variables, as well as the evolution of the kinematic fields retrieved by dual-Doppler analysis. The combination of thermodynamic, kinematic, and inferred microphysical observations supports a hypothesis that the LRR comprises sparse, large hail.
KW - In situ atmospheric observations
KW - Radars/Radar observations
KW - Supercells
UR - http://www.scopus.com/inward/record.url?scp=85040927621&partnerID=8YFLogxK
U2 - 10.1175/MWR-D-17-0201.1
DO - 10.1175/MWR-D-17-0201.1
M3 - Article
AN - SCOPUS:85040927621
VL - 146
SP - 307
EP - 327
JO - Monthly Weather Review
JF - Monthly Weather Review
SN - 0027-0644
IS - 1
ER -