Recent Observations of Tornadoes Using a Mobile, Rapid-Scan, Polarimetric, X-Band, Doppler Radar

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Recent Observations of Tornadoes Using a Mobile, Rapid-Scan, Polarimetric, X-Band, Doppler Radar

ERAD 2014 8th European Conference on Radar in Meteorology and Hydrology Short Abstract #012 Recent observations of tornadoes using a mobile, rapid‐scan, polarimetric, X‐band, Doppler radar Howard Bluestein School of Meteorology, University of Oklahoma, Norman, USA Jeffrey C. Snyder (NSSL, Norman, Oklahoma, U. S. A.) Kyle J. Thiem (University of Oklahoma, Norman, OK, U. S. A.) Zachary B. Wienhoff (University of Oklahoma, Norman, OK, U. S. A.) Jana B. Houser (Department of Geography, Ohio University, Athens, Ohio, U. S. A.) Vivek N. Mahale (University of Oklahoma, Norman, OK, U. S. A.) E‐mail: [email protected] The tornadogenesis process and tornado structure were documented by RaXPol, an X‐band, mobile, polarimetric, rapid‐scan radar (Pazmany et al. 2013) from the University of Oklahoma, in a number of supercells in the Southern Plains during the 2012 and 2013 storm seasons. This presentation will summarize the datasets collected, and highlight and provide an overview of close‐range, volumetric, rapid‐ update observations of two violent tornadoes on 19 May 2013 in central Oklahoma (the Edmond – Carney storm and the Norman – Shawnee storm), and a violent tornado and a weaker, anticyclonic tornado on 31 May 2013, also in central Oklahoma (near El Reno). The fine‐scale structure of a satellite tornado and sub‐ tornado‐scale secondary tornadoes in the violent El Reno tornado will be shown as manifest in the Doppler velocity, radar reflectivity, co‐polar cross correlation coefficient, differential reflectivity, and spectrum width fields. Ground‐relative wind speeds of at least 135 m/s were observed in at least one of these secondary tornadoes. The El Reno tornado’s debris signature in co‐polar cross‐correlation coefficient was as wide as 5 km late in its life, perhaps as a result of debris fallout when the tornado was weakening. Reference: Pazmany, A. L., J. B. Mead, and H. B. Bluestein, J. C. Snyder, and J. B. Houser, 2013: A mobile, rapid‐ scanning, X‐band, polarimetric (RaXPol) Doppler radar system. J. Atmos. Ocean. Technol., 30, 1398 – 1413. .

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