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Radar systems provide the most useful information about the intensity, movement, and characteristics of severe thunderstorms, but are expensive to maintain and require extensive maintenance. In South Africa, some areas are not covered by radar systems, while very few operational radar systems exist in other southern African countries. Despite these shortcomings, all meteorological centers still have to warn the public of pending severe weather events. The Nowcasting Satellite Application Facility (NWC SAF) in Europe developed software that utilizes satellite data to identify and track rapidly developing thunderstorms (RDT). The NWC software was installed at the South African Weather Service in 2014. Initially, the RDT product was validated against lightning data and the results showed that the RDT product could provide very useful information on possible severe or intense convective storms. This study focusses on the effects of including lightning as an ancillary dataset into the algorithms and then validating the RDT product against radar data. Twenty-five summer cases were considered to determine whether the inclusion of lightning data had a positive effect on the accuracy of the RDT product, when compared to radar data. The results of this study show that in the majority of the cases, the inclusion of lightning data was beneficial to the RDT product. On average the Probability of Detection (POD) improved by 6.6%, the Heidke Skill Score (HSS) by 4.6%, and the False alarm ratio (FAR) by 0.1%. To our knowledge, South Africa is the only African country which is running the NWC SAF software operationally and which has performed an evaluation of the product over Africa against observations from radar systems and lightning sensors. The outcomes of this study are very encouraging for other countries in Africa where convection and severe convection often occur and sophisticated data sources are absent. Initial studies over East Africa indicate that the RDT product can benefit operational practices for the nowcasting of severe convection events.

There is a great demand to improve predictions of high‐impact weather across the African continent. This is because of the high frequency of intense convective storms that often produce severe flooding, strong winds and lightning, combined with the vulnerability of people, infrastructure and businesses to such hazards. The skill of numerical weather prediction over Africa is still low, even for lead times of less than 24 hours. Therefore, there is a particular need to deliver nowcasting of events as they occur. However, there remains a widespread lack of provision of nowcasting across Africa and virtually no use of automated nowcasting systems or tools. This limits the ability of national meteorological services to issue warnings and therefore potentially prevent the loss of life and significant financial losses. Coverage by meteorological radars is still very limited, but geostationary satellites provide regular high resolution data of the often large and long‐lived storms. As such, there is an opportunity to improve satellite‐based nowcasting capability in Africa. Work being undertaken as part of the Global Challenges Research Fund African SWIFT (Science for Weather Information and Forecasting Techniques) project is starting to improve the nowcasting of African convective systems and so the ability to provide timely warnings of extreme weather providing a wide range of benefits.