Near Term Convective Precipitation Forecasting using Real-Time Lightning Data

Near Term Convective Precipitation Forecasting using Real-Time Lightning Data

Areas of convective precipitation are often associated with a number of significant hazards such as tornadoes, hail, lightning, wind gusts, and flash floods. A scalable technique is featured to enhance near term precipitation forecasts using real-time lightning data which can assist in timeliness and coverage of convective events and provide reasonable quantitative precipitation forecasts, employing a relationship between lightning flash density and radar with the numerical model forecast parameters. Often we see numerical models have common shortfalls when it comes to convective forecasting such as under forecasting amounts, miscalculating the speed of convective lines, and misplacing the general areas of convective precipitation. Primarily, this is due to a lack of resolution and/or limited initial conditions. When operational forecasters utilize an ensemble of models to manually to make up for these deficiencies, the task can be daunting and there always is a risk an event is missed or not caught until the event has already made a significant impact. The other effect is over forecasting to ensure that missed events are avoided; however, over forecasting can also be detrimental to end users of the forecast data with false alerts to events that sometimes clearly will not happen. The technique displayed within this paper will demonstrate how lightning flash density and radar alters a near term quantitative precipitation forecast initially populated with a blend of numerical models. The result is a far superior first guess field that will include all high impact convective events and if needed, amplify the precipitation amounts that are under forecasted while reducing areas of precipitation not covered by radar and/or have low forecast probability of precipitation (POP).