Utilizing Four Dimensional Lightning and Dual-Polarization Radar to Develop Lightning Initiation Forecast Guidance

Lightning initiation is a major forecast challenge faced by Air Forces 45th Weather Squadron 45 WS, which provides weather support to Cape Canaveral Air Force Station and Kennedy Space Center KSC. Prior studies by Thurmond 2014 and Woodard 2011 have shown that dual-polarization DP radar can be used to identify the presence of hydrometeors indicative of cloud charging, leading to improved lightning initiation forecasts. The 45 WS currently employs empirical lightning initiation forecast rules which state that in-cloud lightning is likely when radar re ectivity meets or exceeds 37.0 dBZ above the 10 C height. This study examined 249 convective cells from March 2012 to March 2014 in order to incorporate DP parameters into existing forecast principles. In-cloud and cloud-to-ground lightning ash data were obtained from the KSC Four Dimensional Lightning Surveillance System, and DP data were obtained from the Melbourne, Florida WSR-88D. Lightning initiation forecast lead times, probabilities of detection, and false alarm rates were compared between candidate DP-based forecast techniques and techniques employed by 45 WS.