The goal of this project is to evaluate the future impact of assimilating data from the Advanced Technology Microwave Sounder (ATMS) and the Crosstrack Infrared Sounder (CrIS) in the forecasting of a significant mesoscale weather event affecting urban centers along the coast of the Gulf of Mexico. The ATMS and the CrIS will be deployed as part of a suite of atmospheric sensors aboard the National Polar-orbiting Operational Environmental Satellite System (NPOESS), as well as the preceding NPOESS Preparatory Project (NPP) satellite.

An Observing System Simulation Experiment (OSSE) methodology is adopted to characterize the uncertainties associated with measurements and field retrievals from sensors in development. The methodology will be based on the procedures adopted by NASA Global Modeling and Assimilation Office (GMAO) and NOAA Environmental Modeling Center (EMC). A nature run (NR) based on the ECMWF model serves as a proxy for real atmospheric and land surface conditions, and is based on a long duration "free run" of a global-scale forecast model. The MM5 is employed to perform a short-term, regional-scale NR nested within the ECMWF NR. Synthetic surface and rawinsonde observations, as well as synthetic ATMS and CrIS observations, will be extracted from the MM5 NR. The WRF model is employed to assimilate the various synthetic data and test the impact of the ATMS / CrIS data. The MM5 and the WRF model are each used to avoid an unrealistically low error bias between the regional-scale NR and the subsequent sensitivity experiments, also known as the "fraternal twin" problem.

It is expected that data transmitted from the ATMS and the CrIS will greatly supplement the existing networks of surface observations, upper-air observations, and satellite observations in the analysis and prediction of tropospheric temperature, humidity, and pressure within a mesoscale weather system.