Enhancing Early Warnings in Africa with MTG Lightning Imager Observations

Africa is one of the global hotspots for thunderstorms and lightning, and their impacts are therefore substantial. Mitigating the effects of thunderstorms in Africa is challenging, as many countries lack state-of-the-art observational infrastructure—such as weather radars—and efficient early warning systems (EWS). Although accurately forecasting tropical thunderstorms remains relatively difficult, observing them is not. Real-time lightning location systems have existed for decades, making it possible to monitor lightning-producing storms. However, these systems, which are based on ground-based sensors, have limitations—especially when there is a need to cover large areas with consistent performance. Satellite-based optical instruments, on the other hand, do not suffer from this drawback.

EUMETSAT has recently launched the optical Lightning Imager (LI) onboard the Meteosat Third Generation (MTG) satellite. The LI observes total lightning in real time within its field of view, covering Europe, the Atlantic Ocean, and Africa. Based on preliminary examinations, the LI provides unprecedented lightning data over Africa. This opens new possibilities for significantly enhancing early warning systems in African countries.

In this study, we provide an initial assessment of the added value of the MTG Lightning Imager for supporting thunderstorm forecasting and early warning systems in East Africa. We focus on three countries participating in the FINKERAT project coordinated by the Finnish Meteorological Institute: Rwanda, Kenya, and Tanzania. Using data from the summer season of 2025, we compare nowcasting and numerical weather prediction (NWP) forecasts against LI observations to evaluate the accuracy and timeliness of convective storm predictions. The results will help to identify strengths and weaknesses in current forecasting practices and illustrate how LI observations can be used to improve the detection and monitoring of severe convective events in the region.