SUPPLEMENTAL BULLETIN ON THIS SUBJECT

This Technical Procedures Bulletin (TPB), written by Lauren L. Morone of the Environmental Modeling Center of the National Centers for Environmental Prediction (NCEP) and Steven J. Pond of the Aviation Weather Center of NCEP, describes the objective and subjective evaluations of the Rapid Update Cycle (RUC) performed prior to its implementation. This bulletin is supplemental to TPB 416.

The RUC is a mesoscale analysis/forecast system that operates on a 3-hour cycle to provide frequent and timely updates of troposheric conditions and short-range (out to 12 hours) forecasts over the lower 48 United States and adjacent areas. The objective evaluations presented here consist of verifications against rawinsonde, profiler and aircraft data. The subjective evaluations were performed by forecasters at the National aviation Weather Advisory Unit in Kansas City, the Hydrometeorological Prediction Center of NCEP (formerly Meteorological Operations Division of the National Meteorological Center), and the Spaceflight Meteorology Group in Houston. Most of subjective evaluations concentrated on the forecasting of aviation parameters.