Polarimetric Tornado Detection

Polarimetric radars are shown to be capable of tornado detection through the recognition of tornadic debris signatures that are characterized by the anomalously low cross-correlation coefficient hv and differential reflectivity ZDR. This capability is demonstrated for three significant tornadic storms that struck the Oklahoma City, Oklahoma, metropolitan area. The first tornadic debris signature, based on the measurements with the National Severe Storms Laboratory’s Cimarron polarimetric radar, was reported for a storm on 3 May 1999. Similar signatures were identified for two significant tornadic events during the Joint Polarization Experiment (JPOLE) in May 2003. The data from these storms were collected with a polarimetric prototype of the Next-Generation Weather Radar (NEXRAD). In addition to a small-scale debris signature, larger-scale polarimetric signatures that might be relevant to tornadogenesis were persistently observed in tornadic supercells. The latter signatures are likely associated with lofted light debris (leaves, grass, dust, etc.) in the inflow region and intense size sorting of hydrometeors in the presence of strong wind shear and circulation.

[1]  Some Inferences About the Updraft Within a Severe Local Storm , 1965 .

[2]  J. Snow.  On the Formation of Particle Sheaths in Columnar Vortices , 1984 .

[3]  J. W. Conway,et al.  A Study of Embryo Production and Hail Growth Using Dual-Doppler and Multiparameter Radars , 1993 .

[4]  A. Zahrai,et al.  The 10 cm wavelength polarimetric weather radar at NOAA's National Severe Storms Laboratory , 1994 .

[5]  Alexander V. Ryzhkov,et al.  Precipitation and Attenuation Measurements at a 10-cm Wavelength , 1995 .

[6]  Lawrence D. Carey,et al.  CSU-CHILL polarimetric radar measurements from a severe hail storm in eastern Colorado , 1998 .

[7]  Dusan Zrnic,et al.  Observations of insects and birds with a polarimetric radar , 1998, IEEE Trans. Geosci. Remote. Sens..

[8]  J. Snow,et al.  Long-Distance Debris Transport by Tornadic Thunderstorms.Part I: The 7 May 1995 Supercell Thunderstorm , 1998 .

[9]  Eugenio Gorgucci,et al.  A procedure to calibrate multiparameter weather radar using properties of the rain medium , 1999, IEEE Trans. Geosci. Remote. Sens..

[10]  Alexander V. Ryzhkov,et al.  Cloud Microphysics Retrieval Using S-Band Dual-Polarization Radar Measurements , 1999 .

[11]  A. Ryzhkov,et al.  Polarimetry for Weather Surveillance Radars , 1999 .

[12]  V. Chandrasekar,et al.  Polarimetric Doppler Weather Radar: Principles and Applications , 2001 .

[13]  Donald W. Burgess,et al.  Radar Observations of the 3 May 1999 Oklahoma City Tornado , 2002 .

[14]  Dusan Zrnic,et al.  Using multiparameter data to calibrate polarimetric weather radars in the presence of a partial beam blockage , 2002, IEEE International Geoscience and Remote Sensing Symposium.

[15]  Jerry M. Straka,et al.  Enhanced polarimetric radar signatures above the melting level in a supercell storm , 2002, IEEE International Geoscience and Remote Sensing Symposium.

[16]  Jerry M. Straka,et al.  Enhanced polarimetric radar signatures above the melting level in a supercell storm , 2002 .

[17]  P. Markowski.  Hook Echoes and Rear-Flank Downdrafts: A Review , 2002 .

[18]  Curtis R. Alexander,et al.  Centrifuging of Hydrometeors and Debris in Tornadoes: Radar-Reflectivity Patterns and Wind-Measurement Errors , 2005 .