Abstract
Precipitation variability in Iraq is commonly evaluated through annual trend analysis; yet the synoptic systems driving this variability remain poorly examined. This study examines the long‐term spatial and temporal trends in the frequency and precipitation contributions of Mediterranean cyclone days and Sudanese low days over Iraq during the period 1954–2023, with both systems identified based on NCEP/NCAR reanalysis data. Using the Mann–Kendall test and Sen's slope estimator, the results reveal a significant decrease in the frequency and precipitation contributions of Mediterranean cyclone days over all parts of Iraq. Conversely, Sudanese low days show increasing frequency and growing precipitation contributions. However, this shift did not compensate for the reduction in precipitation efficiency associated with Mediterranean cyclones, resulting in an overall decline in total precipitation. These results demonstrate a structural reorganization of synoptic drivers across Iraq's transitional climate zone, with implications for drought risk and water resource management across Iraq and other parts of the Middle East.