An introduction to the NCEP Rapid Refresh model data: the next-generation replacement for RUC (Rapid Update Cycle)

Description

The Rapid Update Cycle (RUC), developed by NOAA's Forecast Systems Laboratory and run operationally at the National Centers for Environmental Prediction (NCEP), is an atmospheric prediction system comprised primarily of a numerical forecast model and an analysis system to initialize that model. ARM, via the External Data Center, has collected and archived the hourly analysis data since 1994. Data are available to users in both Grib and netCDF formats. This data set in the ARM Data Archive is the only long-term archive of this model. It has attracted a large variety of users and applications, has found its way into a number of VAPs, and is one of the most requested ARM data sets. Here we want to alert the ARM community of the impending changes in progress at NCEP.

In early 2012, the RUC model is expected to be replaced with the next-generation model called Rapid Refresh (RAP). This model is based on a rapidly refreshing configuration of the Weather Research and Forecasting (WRF) model. The RAP model output products differ from the RUC data in horizontal resolution, domain size, grid type, and variables.

We welcome input from the ARM community on requirements for future ARM data products based on the RAP model output data, e.g., to minimize impact on RUC-dependent processes and analyses or to take full advantage of the new RAP features. Please send requirements or questions to xdc_oper@arm.gov.

For more information on Rapid Refresh, see: http://rapidrefresh.noaa.gov/