A new scheme for predicting intra-cloud and cloud-to-ground flash densities

The advent of cloud resolving atmospheric models has led to improved prediction of cloud and precipitation processes in weather forecast models. In situ, many of these precipitating systems are associated with cloud-to-ground and intra-cloud lightning flashes. Each of these flashes dissipates charges, while producing energy. While it is not possible to use a weather forecast model to predict charging and charge dissipation, one can use the model cloud microphysical and dynamical fields to predict the development, movement, and dissipation of the (potential) energy associated with the implicit charging that occurs due to the forecast cloud-microphysical processes. The dissipation of the energy field converts the potential energy of the electric field into electrical energy that can be counted as “flashes.” The results were quite encouraging; yet the accuracy of the scheme is highly dependent on the model prediction of cloud and precipitation processes. For this reason, lightning observations and lightning predictions were used within a short time window at the start of the forecast to improve the initiation of convection leading to better precipitation and lightning forecasts.