Heavy Rainfall in West Africa and Northern Central Africa

Over the past week (August 5-11), regions including Senegal, Burkina Faso, Nigeria, and Cameroon experienced moderate to heavy rainfall, with localized downpours. In some of these areas, cumulative precipitation reached 50-80 mm, while parts of southern Senegal saw totals exceeding 120 mm (Figure 1).

It is expected that over the next week (August 13-20), influenced by a low vortex (Figure 2), there will be moderate to heavy rainfall from Central Africa to northern West Africa, moving east to west. In particular, parts of northern Cameroon, southern Chad, Nigeria, Guinea, Senegal, Burkina Faso, southern Mali, and western Guinea will experience torrential rain, with localized areas seeing extremely heavy downpours. These rains will be accompanied by severe convective weather such as short-duration intense rainfall and thunderstorms with strong winds. The cumulative rainfall in these regions is generally expected to be between 40 and 90 mm, with some areas receiving 120-160 mm, and localized totals exceeding 200 mm (Figure 3). Attention should be given to the potential for localized heavy rainfall to trigger secondary disasters such as flooding in small and medium-sized rivers and urban waterlogging.

Figure 1 Accumulated Precipitation from August 5 to 11, 2025 (Unit: mm)

Figure 2 500 hPa Geopotential Height (Contour Lines) and 850 hPa Wind Field (Wind Barbs) at 1200 UTC on August 14, 2025

Figure 3 Forecasted Accumulated Rainfall from August 13 to August 20, 2025 (Unit: mm)

Author: Wang Zeyi                                 Reviewer: Niu Ruoyun 

English reviewer:Wang Yi                                                                   Issue approver:Dai Kan