Forecasting cloud-to-ground lightning data with AFWA-MM5 model data using the “Bolt Of Lightning Technique” (BOLT) algorithm

An algorithm was developed to forecast lightning using AFWA MM5 output data. The software GrADS was used to develop the algorithm using an “ad-hoc” methodology. The BOLT algorithm is based upon model forecast instability, cap parameters, and several new parameterizations of the forecast vertical structure of the temperature and moisture profile. According to the algorithm, lightning is produced by boundary layer instability, mid-level instability, and strong dynamic forcing with nearly saturated soundings. A filter that limits over-forecasting of lightning was also developed. Verification metrics were calculated, comparing the BOLT algorithm and the MM5 convective parameterization as a forecast of lightning.