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NOAA’s Climate Prediction Center issues seasonal climate forecasts predicting total precipitation and average air temperature for three-month periods out to a year in advance. The utility of these seasonal forecasts for agricultural applications will depend on forecast characteristics, including dependability and effectiveness. Dependability is defined as the ability of the forecasts to correctly predict future climate probabilities. Effectiveness refers to the ability of the forecasts to provide information beyond that achieved by standard climatological considerations. Measures of dependability and effectiveness are developed for the NOAA probability of exceedance forecasts, and evaluated for the forecasts issued for 1997 through early 2005 for the contiguous U.S. Both measures require that forecasts satisfy, a usefulness threshold of an 8% departure from climatological odds prior to inclusion in the evaluation. Results depend on forecast variable, direction of forecast (wetter/drier, warmer/cooler), season, and forecast lead time. Forecasts for warmer than average conditions are frequent and dependable for most of the U.S.; forecasts for cooler than average conditions are infrequent and rarely dependable. Forecasts for wetter than average conditions are less frequent and less dependable than temperature forecasts; with the exception of Arizona and Florida, forecasts for drier than average conditions are not as frequent or dependable as the wetter forecasts. Overall, in the Desert Southwest, southern and eastern Texas, the Gulf Coast, Florida, and parts of the Pacific Northwest, temperature forecasts have relatively high effectiveness, primarily in November through July, at all lead times. In the same regions, precipitation forecasts have moderate effectiveness in October through February, for lead times up to 6.5 months. For the rest of the U.S., only temperature forecasts show some effectiveness at longer lead times.