This investigation will make use of unique NASA observations of cloud properties from A Train instruments to improve decision making for aviation applications. The key instruments to be used include the CloudSat Cloud Profiling Radar, CALIPSO?s active lidar, and Aqua?s MODIS imaging spectroradiometer. The satellite observations will be used to evaluate numerical weather prediction (NWP) models and aviation products that are essential components of the 4D data cube proposed for NextGen. The project will support activities of the Developmental Testbed Center (DTC), an NCAR/NOAA organization which plays a leading role in evaluating and enhancing NWP systems for operational decision makers, including the rapid refresh models specifically designed to support aviation. Limited observation availability for aviation-related weather variables has slowed improvements of aviation weather forecasts. New satellite observations that directly monitor cloud-scale weather variables and features can significantly advance the identification and implementation of needed improvements of these forecasts. Because many NASA research datasets are not used in operational forecasting processes (e.g., due to limited temporal and spatial sampling), they are independent of routine observations and models used to generate most operational aviation products and are uniquely valuable for use in forecast evaluation. Thus, observation characteristics that traditionally make it difficult to integrate research satellite data into operational products become an asset, not a limitation. The proposed research will create a structure for integrating satellite observations in a framework for meaningful comparisons with NWP model output and specific aviation warning products. Statistical techniques that make full use of the satellite observations for evaluations of forecast products and features will be developed to identify why particular algorithms or numerical parameterizations are sometimes deficient. The research outcome will include new evaluation methods for the DTC, and improved products, models, and operational decision making for NextGen.