The paper presents an attempt to predict hazardous weather events with the use of the Weather Research and Forecasting model (WRF). A new method of parameterization of the spatial density of lightning flashes based on thunderstorm volumes is proposed. Thunderstorm volumes are defined as the number of model cells with radar reflectivity exceeding a certain threshold. The radar reflectivity is calculated from WRF output data, and the threshold value is determined by considering regional features of thunderstorm development in different latitudes. Regression analysis is used to determine the functional relationship that parameterizes the density of lightning discharges based on the volume of convective cells with a certain radar reflectivity. In this work, the developed parameterization was tested and configured for thunderstorms in the Nizhny Novgorod region. We are also searching for the optimal technique for applying the threshold value to the entire model range, or to the area between isotherms within which the separation of electric charge occurs most efficiently. The developed parameterization is verified according to the World Wide Lightning Location Network (WWLLN).