County level interannual climate-yield relationships for winter wheat were examined across a moisture gradient over primarily rainfed agricultural systems in the Columbia Basin of the United States from 1980-2014. Wheat yields were most strongly correlated with energy and moisture availability during the latter stages of crop development. Estimated actual evapotranspiration calibrated for winter wheat was typically the best predictor of interannual yield variability at the county level, with the strongest relationships for counties with intermediate amounts of mean annual precipitation. Crop yields were negatively impacted by warmer temperatures during the latter stages of crop development, particularly in the climatologically cooler counties as delayed crop phenology results in warmer temperatures during phenostages when crops are most sensitive. A variety of multi-variate statistical models explain an average of 29-37% of interannual county-level yield variance over the Columbia Basin, yet show spatial heterogeneities in climate yield relationships suggesting the importance of subregional climate-crop modeling.