This study aims to analyze variability and trends of temperature and rainfall over three agro-ecological zones (AEZs) in Central Ethiopia. Gridded rainfall and temperature data, recorded on daily basis for 35 years (1979 - 2013) at 30 meteorological stations, were used for analysis. While Mann–Kendall test was applied to analyze the trends in rainfall and temperature, Sen’s slope estimator was used to determine the magnitude of change. The study detected an upward trend of 0.07°C/annum (p < 0.001) in mean annual maximum temperature at Kolla AEZ. It also showed an upward trend of 0.06/year (p < 0.001) for both Dega and Woina Dega AEZs. Mean annual minimum temperature exhibited an upward trend of 0.03°C/year at Kolla (p < 0.001), Woina Dega (p < 0.05), and Dega (p < 0.01), signifying a 1.05°C increase between 1979 and 2013. Results from precipitation concentration index (PCI) revealed highest percentage (97.1%) of irregular distributions in annual rainfall pattern at Kolla AEZ, followed by Woina Dega (82.9%). Standardized rainfall anomalies (SRA) computed in the study also showed higher percentage (28.6%) of drought in Kolla AEZ, which experienced drought once in every 3 or 4 years. The study revealed negative annual rainfall anomalies for 18 years in Kolla and 16 years in both Dega and Woina Dega AEZs. The reduced precipitation and rise in temperature could trigger wide-ranging influences on agricultural practices and crop production of smallholder farmers. Policymakers and stakeholders should give priority in designing and introducing pro-poor plus geographically differentiated adaptive strategies.