The Rapid Refresh (RR) is scheduled to replace the Rapid Update Cycle (RUC) as the primary source of numerical weather prediction forecast guidance for aviation in 2009. The RR will be run over a domain covering essentially all of North America, over 2.5 times the size of the current RUC domain. Testing of a 1-h cycled, full-domain version of the RR at the Global Systems Division, using the Gridpoint Statistical Interpolation analysis and RUC-like physics in the Weather Research and Forecast Model, will soon begin.

In this paper, we will briefly review the current status of RR development, show case examples of forecasts of aviation impact variables from the GSD test version of the RR and summarize strengths and weaknesses in forecast performance revealed by this testing.