Changes to the Operational ''Early'' Eta Analysis / Forecast System at the National Centers for Environmental Prediction

摘要: This note describes changes that have been made to the National Centers for Environmental Prediction ( NCEP ) operational ‘‘early’’ eta model. The are 1 an decrease in horizontal grid spacing from 80 48 km, 2 incorporation of a cloud prediction scheme, 3 replacement original static analysis system with 12-h intermittent data assimilation using model, and 4 use satellite-sensed total column water optimum interpolation analysis. When tested separately, each four improved model performance. A quantitative subjective evaluation full upgrade package during March April 1995 indicated 48-km was more skillful than 80-km predicting intensity movement large-scale weather systems. In addition, severe mesoscale precipitation events either nested or global spectral ‐ period. implementation this new version early performed October 1995.