A long-range forecasting technique, based on a physical model that emphasizes thermodynamics, is applied to the prediction of anomalies of temperature and precipitation for the Northern Hemisphere. Monthly forecasts are initialized with the sea surface temperature, 700 mb temperature and surface albedo, including variable snow-ice conditions. Application to the hot spell and drought in the summer of 1980 for the contiguous United States shows very encouraging skill when verified for the standard 100-station NOAA grid.
1 Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, México, 20, D.F.
2 Lamont-Doherty Geological Observatory of Columbia University, Palisades, N.Y. 10964.