Evaluation of Stage IV precipitation estimates over the eastern United States

Gauge calibrated radar estimates of daily precipitation are compared with daily observed values from National Weather Service Cooperative Observer Network (COOP) stations to evaluate the ability of NCEP multi-sensor precipitation estimates (MPE) for the eastern United States. The estimates are evaluated by season, observed intensity, and location. In addition, the estimates are evaluated for distinctions between inland locations and near shore locations. Results of this study indicate a north-south gradient in the error of MPE and a seasonal pattern with the highest error in summer and lowest error in winter. The results of this study also indicate higher error for precipitation events occurring near the coastline of the Atlantic Ocean and Gulf of Mexico, and that small precipitation amounts are overestimated more frequently than large amounts are underestimated. These results suggest MPE has lesser ability to estimate convective-scale precipitation as compared to precipitation variations at larger scales.