Impact of the Environmental Low-Level Wind Profile on Ensemble Forecasts of the 4 May 2007 Greensburg, Kansas, Tornadic Storm and Associated Mesocyclones

AbstractThe early tornadic phase of the Greensburg, Kansas, supercell on the evening of 4 May 2007 is simulated using a set of storm-scale (1-km horizontal grid spacing) 30-member ensemble Kalman filter (EnKF) data assimilation and forecast experiments. The Next Generation Weather Radar (NEXRAD) level-II radar data from the Dodge City, Kansas (KDDC), Weather Surveillance Radar-1988 Doppler (WSR-88D) are assimilated into the National Severe Storms Laboratory (NSSL) Collaborative Model for Multiscale Atmospheric Simulation (COMMAS). The initially horizontally homogeneous environments are initialized from one of three reconstructed soundings representative of the early tornadic phase of the storm, when a low-level jet (LLJ) was intensifying. To isolate the impact of the low-level wind profile, 0–3.5-km AGL wind profiles from Vance Air Force Base, Oklahoma (KVNX), WSR-88D velocity-azimuth display (VAD) analyses at 0130, 0200, and 0230 UTC are used. A sophisticated, double-moment bulk ice microphysics scheme i...

[1]  Louis J. Wicker,et al.  Additive Noise for Storm-Scale Ensemble Data Assimilation , 2009 .

[2]  C. Snyder,et al.  A Multicase Comparative Assessment of the Ensemble Kalman Filter for Assimilation of Radar Observations. Part I: Storm-Scale Analyses , 2009 .

[3]  Jerry M. Straka,et al.  Assimilation of Simulated Polarimetric Radar Data for a Convective Storm Using the Ensemble Kalman Filter. Part II: Impact of Polarimetric Data on Storm Analysis , 2008 .

[4]  H. D. Orville,et al.  Bulk Parameterization of the Snow Field in a Cloud Model , 1983 .

[5]  Louis J. Wicker,et al.  Wind and Temperature Retrievals in the 17 May 1981 Arcadia, Oklahoma, Supercell: Ensemble Kalman Filter Experiments , 2004 .

[6]  Ming Xue,et al.  Effects of microphysical drop size distribution on tornadogenesis in supercell thunderstorms , 2008 .

[7]  H. Bluestein.  The Formation and Early Evolution of the Greensburg, Kansas, Tornadic Supercell on 4 May 2007 , 2009 .

[8]  S. Cohn,et al.  Ooce Note Series on Global Modeling and Data Assimilation Construction of Correlation Functions in Two and Three Dimensions and Convolution Covariance Functions , 2022 .

[9]  Conrad L. Ziegler,et al.  Retrieval of Thermal and Microphysical Variables in Observed Convective Storms. , 1985 .

[10]  David J. Stensrud,et al.  Effects of Upper-Level Shear on the Structure and Maintenance of Strong Quasi-Linear Mesoscale Convective Systems , 2006 .

[11]  Chris Snyder,et al.  A Multicase Comparative Assessment of the Ensemble Kalman Filter for Assimilation of Radar Observations. Part II: Short-Range Ensemble Forecasts , 2010 .

[12]  David J. Stensrud,et al.  Importance of Horizontally Inhomogeneous Environmental Initial Conditions to Ensemble Storm-Scale Radar Data Assimilation and Very Short-Range Forecasts , 2010 .

[13]  M. Yau,et al.  A Multimoment Bulk Microphysics Parameterization. Part IV: Sensitivity Experiments , 2006 .

[14]  G. Thompson,et al.  Impact of Cloud Microphysics on the Development of Trailing Stratiform Precipitation in a Simulated Squall Line: Comparison of One- and Two-Moment Schemes , 2009 .

[15]  Stanley G. Benjamin,et al.  CONVECTIVE-SCALE WARN-ON-FORECAST SYSTEM: A vision for 2020 , 2009 .

[16]  Erik N. Rasmussen,et al.  Precipitation Uncertainty Due to Variations in Precipitation Particle Parameters within a Simple Microphysics Scheme , 2004 .

[17]  Louis J. Wicker,et al.  Simulation and Analysis of Tornado Development and Decay within a Three-Dimensional Supercell Thunderstorm , 1995 .

[18]  Daniel T. Dawson,et al.  Comparison of Evaporation and Cold Pool Development between Single-moment and Multi-moment Bulk Microphysics Schemes in Idealized Simulations of Tornadic Thunderstorms , 2009 .

[19]  S. Barnes,et al.  A Technique for Maximizing Details in Numerical Weather Map Analysis , 1964 .

[20]  Juanzhen Sun,et al.  Real-Time Low-Level Wind and Temperature Analysis Using Single WSR-88D Data , 2001 .

[21]  Eric C. Bruning,et al.  Simulated Electrification of a Small Thunderstorm with Two-Moment Bulk Microphysics , 2010 .

[22]  Chris Snyder,et al.  A Comparison between the 4DVAR and the Ensemble Kalman Filter Techniques for Radar Data Assimilation , 2005 .

[23]  Jeffrey L. Anderson.  Spatially and temporally varying adaptive covariance inflation for ensemble filters , 2009 .

[24]  Louis J. Wicker,et al.  Ensemble Kalman Filter Assimilation of Radar Observations of the 8 May 2003 Oklahoma City Supercell: Influences of Reflectivity Observations on Storm-Scale Analyses , 2011 .

[25]  William R. Cotton,et al.  The Impact of Hail Size on Simulated Supercell Storms , 2004 .