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1979 ; Doswell 1985 ). It has been suggested that the temperature field in and near a low-level mesocyclone, particularly that associated with the rear-flank downdraft (RFD), may play a role in tornadogenesis ( Davies-Jones et al. 2001 ; Markowski et al. 2002 ). Previous field studies tested this hypothesis using mobile in situ instruments to measure thermodynamic variables in and around the tornado’s parent mesocyclone. While the collection of mobile in situ data was often successful, the
1979 ; Doswell 1985 ). It has been suggested that the temperature field in and near a low-level mesocyclone, particularly that associated with the rear-flank downdraft (RFD), may play a role in tornadogenesis ( Davies-Jones et al. 2001 ; Markowski et al. 2002 ). Previous field studies tested this hypothesis using mobile in situ instruments to measure thermodynamic variables in and around the tornado’s parent mesocyclone. While the collection of mobile in situ data was often successful, the
Polarimetric Radar Signatures of a Rare Tornado Event over South Koreaal. 2006 ; Byko et al. 2009 ). The DRC typically occurs prior to the development of the hook echo. The DRC signatures can be used to detect tornadogenesis. DRCs may or may not be associated with tornadic storms. Rasmussen et al. (2006) performed the preliminary study on DRCs in which they described the characteristics of DRC in convective storms. They also discussed the frequency of occurrence of DRCs prior to tornadic supercell storms. Subsequently, Kennedy et al. (2007) presented a
al. 2006 ; Byko et al. 2009 ). The DRC typically occurs prior to the development of the hook echo. The DRC signatures can be used to detect tornadogenesis. DRCs may or may not be associated with tornadic storms. Rasmussen et al. (2006) performed the preliminary study on DRCs in which they described the characteristics of DRC in convective storms. They also discussed the frequency of occurrence of DRCs prior to tornadic supercell storms. Subsequently, Kennedy et al. (2007) presented a
A Variational Method for Filling in Missing Data in Doppler Velocity Fields-in fields utilizing a histogram and a linear regression model. Figure 9 presents KOUN WSR-88D scans of ground-relative base Doppler velocity ( V r ), base reflectivity ( Z ) of and base spectrum width ( σ υ ) of the violent El Reno tornado as collected with superresolution (0.5° azimuthal interval and 250-m range increment) at the 0.97° launch angle at 2311:04 UTC 31 May 2013. Tornadogenesis, tornado evolution, photogrammetric and polarimetric analyses, and aerial damage survey in the El Reno tornadic
-in fields utilizing a histogram and a linear regression model. Figure 9 presents KOUN WSR-88D scans of ground-relative base Doppler velocity ( V r ), base reflectivity ( Z ) of and base spectrum width ( σ υ ) of the violent El Reno tornado as collected with superresolution (0.5° azimuthal interval and 250-m range increment) at the 0.97° launch angle at 2311:04 UTC 31 May 2013. Tornadogenesis, tornado evolution, photogrammetric and polarimetric analyses, and aerial damage survey in the El Reno tornadic
detection of increasing convergence beneath a mesocyclone aloft ( Burgess 2004 ). The solutions roughly model tornadogenesis without a dynamic pipe effect ( Trapp and Davies-Jones 1997 ). In contrast, tornadoes that form with a dynamic pipe effect descend from aloft and develop more slowly, allowing the issuance of warnings with long lead times based on TVS detection. We perform experiments with different values of the constant eddy viscosity and the uniform convergence ( section 3 ) to obtain tornadoes
detection of increasing convergence beneath a mesocyclone aloft ( Burgess 2004 ). The solutions roughly model tornadogenesis without a dynamic pipe effect ( Trapp and Davies-Jones 1997 ). In contrast, tornadoes that form with a dynamic pipe effect descend from aloft and develop more slowly, allowing the issuance of warnings with long lead times based on TVS detection. We perform experiments with different values of the constant eddy viscosity and the uniform convergence ( section 3 ) to obtain tornadoes
Exploring Tornadic Debris Signature Hypotheses Using Radar Simulations and Large-Eddy Simulationswith leaves, one with wood boards, and one with metal sheets. Raindrops are randomly populated in the SimRadar domain at the onset of a simulation, while debris are initialized at the bottom of the domain. However, not all debris are lofted above 89 m AGL. To illustrate this, the debris count with height is plotted at the end of the tornadogenesis case ( Fig. 1 ). Regardless of debris type, only a fraction of debris are lofted to the lowest height of the radar beam. Specifically, only 19.74% of
with leaves, one with wood boards, and one with metal sheets. Raindrops are randomly populated in the SimRadar domain at the onset of a simulation, while debris are initialized at the bottom of the domain. However, not all debris are lofted above 89 m AGL. To illustrate this, the debris count with height is plotted at the end of the tornadogenesis case ( Fig. 1 ). Regardless of debris type, only a fraction of debris are lofted to the lowest height of the radar beam. Specifically, only 19.74% of
deployment season during VORTEX. These data are being analyzed and early results are presented elsewhere ( Wurman et al. 1996a , Wurman et al. 1996b ; Straka et al. 1996 ). Representative data from a tornadogenesis event that occurred near Rolla, Kansas, illustrate the capabilities of the DOW ( Fig. 12 ). For the first time, high-resolution detail is revealed in the hook echo and the coil-like signature of the nascent tornado. A moderately intense velocity couplet associated with the parent circulation
deployment season during VORTEX. These data are being analyzed and early results are presented elsewhere ( Wurman et al. 1996a , Wurman et al. 1996b ; Straka et al. 1996 ). Representative data from a tornadogenesis event that occurred near Rolla, Kansas, illustrate the capabilities of the DOW ( Fig. 12 ). For the first time, high-resolution detail is revealed in the hook echo and the coil-like signature of the nascent tornado. A moderately intense velocity couplet associated with the parent circulation
A Trajectory Mapping Technique for the Visualization and Analysis of Three-Dimensional Flow in Supercell Stormsmesocyclogenesis . J. Atmos. Sci. , 56 , 2045 – 2069 , doi: 10.1175/1520-0469(1999)056<2045:ANSOCM>2.0.CO;2 . 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 , 1263 – 1274 , doi: 10.1175/BAMS-86-9-1263 . Brandes , E. A. , 1978 : Mesocyclone evolution and tornadogenesis: Some observations . Mon. Wea. Rev. , 106 , 995 – 1011 , doi: 10
mesocyclogenesis . J. Atmos. Sci. , 56 , 2045 – 2069 , doi: 10.1175/1520-0469(1999)056<2045:ANSOCM>2.0.CO;2 . 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 , 1263 – 1274 , doi: 10.1175/BAMS-86-9-1263 . Brandes , E. A. , 1978 : Mesocyclone evolution and tornadogenesis: Some observations . Mon. Wea. Rev. , 106 , 995 – 1011 , doi: 10
High-Resolution, Rapid-Scan Dual-Doppler Retrievals of Vertical Velocity in a Simulated Supercell-use tables. The simulation includes a period of cyclical tornadogenesis ( Fig. 1 ; see also Fig. 9d of Schenkman et al. 2014 ), which is selected for analysis here. Fig . 1. “True” horizontal winds (vectors) and vertical winds (color fill) at 3 km above radar level, valid at the analysis time, within the provisional domain for the ARPS simulation. Hatched regions denote areas where the radar reflectivity is less than 5 dB Z . Occluded and developing tornado locations are denoted by “T1” and “T2
-use tables. The simulation includes a period of cyclical tornadogenesis ( Fig. 1 ; see also Fig. 9d of Schenkman et al. 2014 ), which is selected for analysis here. Fig . 1. “True” horizontal winds (vectors) and vertical winds (color fill) at 3 km above radar level, valid at the analysis time, within the provisional domain for the ARPS simulation. Hatched regions denote areas where the radar reflectivity is less than 5 dB Z . Occluded and developing tornado locations are denoted by “T1” and “T2
An Automated Python Algorithm to Quantify Z
DR Arc and K
DP–Z
DR Separation Signatures in Supercellsthe progression of supercell and tornado life cycles. Palmer et al. (2011) observed a cyclic pattern of Z DR arc evolution in a violently tornadic supercell during the 10 May 2010 tornado outbreak in Oklahoma, with the Z DR arc extending back toward the hook echo leading up to tornadogenesis and weakening around tornado demise and occlusion, only to strengthen again as a new mesocyclone became established and produced another tornado. Kumjian et al. (2010) documented a similar pattern of
the progression of supercell and tornado life cycles. Palmer et al. (2011) observed a cyclic pattern of Z DR arc evolution in a violently tornadic supercell during the 10 May 2010 tornado outbreak in Oklahoma, with the Z DR arc extending back toward the hook echo leading up to tornadogenesis and weakening around tornado demise and occlusion, only to strengthen again as a new mesocyclone became established and produced another tornado. Kumjian et al. (2010) documented a similar pattern of
.1175/1520-0450(1964)003<0396:ATFMDI>2.0.CO;2 Beck, J. R. , Schroeder J. L. , and Wurman J. M. , 2006 : High-resolution dual-Doppler analyses of the 29 May 2001 Kress, Texas, cyclic supercell. Mon. Wea. Rev. , 134 , 3125 – 3148 . 10.1175/MWR3246.1 Brandes, E. A. , 1978 : Mesocyclone evolution and tornadogenesis: Some observations. Mon. Wea. Rev. , 106 , 995 – 1011 . 10.1175/1520-0493(1978)106<0995:MEATSO>2.0.CO;2 Clark, T. L. , Harris F. I. , and Mohr C. G. , 1980 : Errors in wind fields derived from
.1175/1520-0450(1964)003<0396:ATFMDI>2.0.CO;2 Beck, J. R. , Schroeder J. L. , and Wurman J. M. , 2006 : High-resolution dual-Doppler analyses of the 29 May 2001 Kress, Texas, cyclic supercell. Mon. Wea. Rev. , 134 , 3125 – 3148 . 10.1175/MWR3246.1 Brandes, E. A. , 1978 : Mesocyclone evolution and tornadogenesis: Some observations. Mon. Wea. Rev. , 106 , 995 – 1011 . 10.1175/1520-0493(1978)106<0995:MEATSO>2.0.CO;2 Clark, T. L. , Harris F. I. , and Mohr C. G. , 1980 : Errors in wind fields derived from
