A generalized cloud analysis package with both stable and convective cloud modules has been developed and is being used within both the Rapid Update Cycle (RUC) and Rapid Refresh (RR) regional assimilation systems. Within the operational RUC 3DVAR, the cloud analysis package utilizes NESDIS GOES satellite-derived cloud top pressure and temperature data, as well as surface METAR cloud and visibility information. An upgrade that will add the use of radar reflectivity data is slated for RUC operational implementation at NCEP in fall of 2008. Within the Rapid Refresh system (currently in real-time testing at ESRL/GSD as a planned replacement for RUC in 2010), the cloud analysis has been integrated into the Gridpoint Statistical Interpolation (GSI) analysis software. In addition to use of satellite products in the cloud analysis, the GSI analysis includes a full satellite radiance assimilation procedure (see related presentation by Devenyi et al).

For both the RUC and Rapid Refresh experimental forecast cycles (run at ESRL/ GSD), additional data sets, including lightning and satellite-derived liquid and ice water path products, are being tested. The liquid and ice water path fields are derived by the NASA Langley Research Center in real-time utilizing multiple GOES channels. More recently, work in conjunction with Joint Center for Satellite Data Assimilation (JCSDA) has been initiated to test the direct use of GOES imager data to obtain estimated cloud top pressures within the generalized cloud analysis.

We will provide a brief overview of the cloud analysis system, then describe the specific procedures for using the various satellite fields and merging the information from the various cloud data sources and lastly illustrate the impact of these various data sources. One focus of our presentation will be on the use of the NASA Langley experimental water and ice path fields for two specific analysis challenges, icing and marine stratus. In addition, we will present preliminary results from work to directly compute cloud top pressures from GOES imager data within the GSI cloud analysis.