We evaluated the historical and projected trends in climate and vegetation relevant to the Coronado National Forest in southeast Arizona, USA. We then applied this information in an assessment of the vulnerability of 30 species of terrestrial vertebrates on the Coronado National Forest to the potential effects of future climate change. We used a pilot version of a decision-support tool developed by the U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station that produces scores that represent relative measures of vulnerability to climate change as related to habitat, physiology, phenology, and biotic interactions.