A comparison of high resolution tornado surveys to Doppler radar observed mesocyclone parameters: 2011-2012 case studies

Past research has given bleak assessment on the ability of the WSR-88D to quantitatively estimate tornado peak wind speed based on an analysis of the 1999 May 03 Bridgecreek to Moore, OK tornado (e.g., Burgess et al. 2002). Since that time, there have been significant advances in tornado surveying methods and the resolution of the WSR-88D base data. In addition, Toth and Trapp (2011) have shown rather encouraging results in an intercomparison of vortex strength detected by Doppler On Wheels and the WSR-88D. These developments have given us an opportunity to re-evaluate the relationship between the strength of the mesocyclone detections and the strength of tornadoes. Two questions need to be answered. The first is whether or not we can relate the maximum surveyed damage intensity to that of the maximum strength of the output parameters of the Mesocyclone Detection Algorithm? Kingfield et al. (2012) is evaluating the first question. The second question is whether we can evaluate this relationship on a temporal scale that can be useful to warning forecasters? To begin developing an answer for this, we assess several events where high resolution damage surveys are available nearby a WSR-88D from the year 2011 and 2012. We will discuss the results and implications for expanding this work.

References: Burgess, D. W., M. A. Magsig, J. Wurman, D. C. Dowell, Y. Richardson, 2002: Radar Observations of the 3 May 1999 Oklahoma City Tornado. Wea. Forecasting, 17, 456–471.

Toth, M., R. J. Trapp, J. Wurman, and K. A. Kosiba, 2011: Enhancing tornado intensity estimates with Doppler radar. 35th Conf. Radar Meteorology, Pittsburg, PA, 4B.1.

Kingfield, D., J. G. LaDue, Ortega, K. L., 2012: An evaluation of tornado intensity using velocity and strength attributes from the WSR-88D Mesocyclone Detection Algorithm, 26th Conf. Severe Local Storms, Nashville, TN.