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The historical response of plant populations to climate variation may provide important clues about the sensitivity and future performance of populations to changes in climate regimes. Such an understanding is necessary for prioritizing short- and long-term management efforts. To examine the relationship between annual climate and changes in cover of common grasses and sagebrush, we compiled long-term records of cover data from permanent vegetation plots across the western United States. Specifically, we asked 1) how has the cover of key sagebrush steppe species responded to historical inter-annual variation in climate, 2) under what climate conditions does cover increase or decrease for each species, and 3) how consistent are species responses across our study region? We performed the analysis by comparing the change in species' cover at each site in each year to the climate conditions experienced during that year. Cover of Artemisia tridentata decreased significantly in response to spring temperatures. Conversely, cover of Bromus tectorum and Poa secunda increased mostly in wetter years. Three other species (A. tripartita, Pseudoroegnaria spicata, and Hesperostipa comata) showed very weak responses to annual climate. This analysis shows that species commonly found together may differ in their response to annual climate variation. The generally weak responses to annual climate variation we observed contrasts with the strong sensitivity to climate predicted by species distribution models and suggests that species' responses to climate may require long-term changes in climate or may be driven by other indirect effects of climate (such as fire frequency). This study outlines a method for using easily collected long-term data to investigate short-term population responses to climate variation; a potentially useful approach for managers tasked with understanding short-term consequences of climate variation.