Nile Basin Seasonal Hydrological Outlook: June-July-August-September 2025 Season

The Nile Basin Initiative (NBI) has released its Seasonal Hydrological Forecast and Outlook for the period of June - July– August- September (JJAS) 2025 Season. This follows the release of the Seasonal Climate Outlook for June-September 2025 Season by the Intergovernmental Authority on Development (IGAD) Climate Prediction and Applications Centre (ICPAC) for the Great Horn of Africa on 20th May 2025 at the 70th Greater Horn of Africa Climate Outlook Forum (69th GHACOF) in Addis Ababa Ethiopia. The Climate Outlook predicted 55% probability of above-normal rainfall over central Sudan, eastern South Sudan, northern and southwestern Ethiopia, western Kenya, and eastern Uganda. Also, experience wetter-than-average conditions with about 45% chance is expected in western Uganda, South Sudan, southern Sudan, and western. Conversely, there is a high chance of below-average rainfall over northwestern South Sudan, and southeastern Ethiopia. The released Climate Outlook has a wider implication in the basin hydrology.

Therefore, the Nile Basin Regional Expert Working Group (REWG) on Hydrology and Advisory has used the ICPAC’s seasonal climate outlook to generate the Nile Basin Seasonal Hydrological Outlook for Jun-September 2025 Season. The Outlook is an output of expert assessment, analysis and model simulations by the experts during a workshop held on 21st and 22nd May 2025 alongside ICPAC’s 70th GHACOF in Addis Ababa Ethiopia. The experts Outlook provides a comprehensive analysis of the implications of the climate projections on basin hydrology and the activities in the basin. It also includes flood and drought risk analyses and suggested areas of interventions/ mitigation at country and basin-wide levels. The objective of the Hydrological Outlook is to support Member States and stakeholders in the planning interventions for risk reduction and disaster preparedness for the period of June-September 2025.