Hydrological Assessment of Increased Precipitation in the Southwestern Region of Saudi Arabia

Water scarcity is a persistent challenge in arid and semi-arid environments, including the southwestern region of Saudi Arabia where water availability is strongly controlled by precipitation variability. This study provides a hydrological assessment of increased precipitation during 2022–2025 relative to a baseline period (2015–2021) using integrated satellite-derived and ground-based observations.

The analysis quantifies changes in precipitation magnitude, frequency, and spatial distribution and evaluates resulting watershed-scale responses through hydrological modeling. Key hydrological outcomes examined include surface runoff generation, streamflow behavior, soil moisture dynamics, and potential groundwater recharge. Model outputs are analyzed to determine how precipitation anomalies propagate through catchment processes and alter water availability across diverse topographic and land-surface conditions.

Results show that the 2022–2025 period is associated with measurable increases in hydrological response where cloud seeding operations occurred, including higher runoff volumes and enhanced streamflow in several catchments, with variability driven by watershed characteristics and antecedent conditions. The study discusses uncertainties related to interannual climate variability, data limitations, and model parameter sensitivity, and identifies implications for water resources planning and flood-risk management in southwestern Saudi Arabia. These findings support evidence-based management by linking precipitation changes to hydrological behavior in a water-stressed region.