Eugenia Enriqueta Kálnay de Rivas (born 1 October 1942) is an Argentine meteorologist and a Distinguished University Professor of Atmospheric and Oceanic Science, which is part of the University of Maryland College of Computer, Mathematical, and Natural Sciences at the University of Maryland, College Park in the United States. In 1996, Kálnay was elected a member of the National Academy of Engineering for advances in understanding atmospheric dynamics, numerical modeling, and atmospheric predictability and in the quality of U.S. operational weather forecasts.