Rainfall is an important hydrological cycle and has major influence on the environment and agricultural productivity all over the world.Western Amhara,heavily relies on agriculture,making rainfall variability a critical concern.There is not recent study on characterization of past and future main rainy season (Kiremt/June September) over Western Amhara region,Ethiopia.Hence,this research investigates historical and projected changes in rainfall during Kiremt season (June-September) to understand the implications for water resources and agricultural productivity.We analyzed observational data from 1991-2020 and projected future rainfall (2021 2100) using Coupled Model Inter comparison Project phase 6 Global Climate Models (CMIP6 GCMs),by evaluating their performance against ground observations for the period 1995 2014.Applying appropriate statistical metrics for model performance evaluation,and the ensemble mean of top three best performing CMIP6 GCMs were selected separately for future daily,monthly ,and seasonal rainfall study under different Shared Socioeconomic Pathways (SSPs).Our findings reveal a statistically significant increase in the cessation date of the kiremt season during the past period.Future projections indicate that,under various SSP scenarios,the onset date of the kiremt season will be delayed,while the cessation date will advance,resulting in a shorter growing period.Interestingly,despite the shortened season,projections suggest an increase in total seasonal rainfall under most scenarios.These findings highlight the need for adaptation strategies to mitigate the potential impacts of changing rainfall patterns on agriculture and water resources in Western Amhara region,Ethiopia.