Probabilistic Detection of Low Cloud Ceilings and Cloud Phase Determination Using the GOES-R Approach: Algorithm Description and Comparison to FRAMICE Observations Michael Pavolonis (NOAA/NESDIS) Corey Calvert (UW- CIMSS) The Advanced Baseline Imager (ABI) on board the next generation of Geostationary Operational Environmental Satellites (GOES-R) will provide spectral, spatial, and temporal capabilities that significantly exceed those offered by the current GOES Imager. These new instrument capabilities, in tandem with other data sets (e.g. NWP), can be used to generate a variety of products that are capable of automatically detecting and characterizing hazards such as fog/low cloud. Using the Moderate Resolution Imaging Spectroradiometer (MODIS) and the current GOES imager as proxies for the GOES-R ABI, it will be shown that quantitative products, such as the probability of Instrument Flight Rules (IFR) and cloud thermodynamic phase can be generated and are useful for real-time fog/low cloud hazard detection and assessment. This talk will describe the approach, developed by NOAA’s GOES-R Algorithm Working Group (AWG), for detecting low cloud ceilings and determining cloud phase using a combination of satellite, NWP, and other ancillary data. In addition, preliminary results from comparisons to FRAM-ICE observations will be shown.