Globally, many species’ distributions are shifting in response to contemporary climate change. However, the direction and rate of shifts remain difficult to predict, impeding managers’ abilities to optimize resource allocation. Here, we developed a new approach for forecasting species range‐limit shifts that requires only abundance data along environmental (for example, elevational) gradients. We posited that the distribution of species’ abundances could offer insights into the potential for future range‐limit shifts. We then tested this prediction using data from several transect studies that compared historical and contemporary distributions. Consistent with our prediction, we found that strong asymmetry in abundance distributions (that is, “leaning” distributions) indeed preceded species’ lower‐limit range shifts. Accordingly, surveying abundances along environmental gradients may represent a promising, cost‐effective method for forecasting local shifts. Ideally, this approach will be incorporated by practitioners into species‐specific management planning and will inform on‐the‐ground conservation efforts.