Forecasting Lightning Initiation Utilizing Dual-Polarization Radar Parameters over Washington, D.C.
Date of Award
Master of Science
Department of Engineering Physics
Omar A. Nava, PhD.
Accurate forecasts of thunderstorms are vital to space launch, aviation, and public safety. Prior studies by Woodard (2011), Thurmond (2014), and Travis (2015) show that dual-polarization radar can be utilized to identify the presence of hydrometeors necessary for cloud charging. These studies emphasized that a combination of radar reflectivity (Z) and differential reflectivity (ZDR) predictors have the potential to improve forecast skill of lightning initiation over methods that rely on Z alone (Roeder and Pinder, 1998; Yang and King, 2010). Travis (2015) discovered two parameters, when used together, produced the best results: Z ≥ 36.5 dBZ and ZDR ≥ 0.31 at the -10 °C height. Travis (2015) also highlighted that ZDR is the preferred parameter to use in conjunction with Z as elevated ZDR values are indicative of supercooled water droplets and wet ice particles which are important to the overall electrification process occurring within a cloud. This study applied the lightning initiation prediction method developed for Cape Canaveral Air Force Station (CCAFS) and NASA Kennedy Space Center (KSC) in Travis (2015) to a new location. The method was tested on 100 isolated, warm season thunderstorms spanning 5 years in and around the Washington D.C. area. Forecast metrics and lead times were calculated and com- pared to the results of Travis (2015). The results of this study concluded that the lightning initiation prediction algorithm from Travis (2015) for CCAFS/KSC does not perform well for the Washington, D.C. area. This implies that one lightning initiation prediction method cannot be applied across the entire national NEXRAD network.
DTIC Accession Number
Olsen, Sarah A., "Forecasting Lightning Initiation Utilizing Dual-Polarization Radar Parameters over Washington, D.C." (2018). Theses and Dissertations. 1752.