Cyanobacterial harmful algal blooms (CyanoHABs) are a global problem affecting public and environmental health. The goal of this project is to develop a capability, the Modeling and Forecasting System (M&FS), to identify, document, and climatologically forecast CyanoHABs in major water bodies to aid environmental and public health managers in planning and response. This capability involves: (1) Routinely identifying blooms; (2) Forecasting CyanoHAB events; and (3) Transferring these results to health and environmental management agencies. The project will combine environmental, meteorological, and disease surveillance data with color and temperature satellite data (e.g., from MODIS and VIIRS). Florida and the Great Lakes are the initial regions of interest, but the modeling and prediction products will be evaluated for their applicability in other coastal and inland areas. Successful implementation of this project will reduce monitoring costs, improve water management practices, and reduce public health impacts of CyanoHABs. The proposed project addresses Public Health, Oceans and Human Health, and Water Quality Assessment concerns of the Decision Support program. The M&FS will be developed by integrating NASA products into detection and forecast capabilities at the National Oceanic and Atmospheric Administration (NOAA); data communication and integration capabilities at the Centers for Disease Control and Prevention (CDC) through the Harmful Algal Bloom Illness Surveillance System (HABISS); and communication, education, and outreach materials programs of the Florida Department of Health (FDOH). NOAA, through the Center of Excellence for Great Lakes and Human Health, is refining models for detection and prediction of cyanobacterial bloom development, conducting outreach stakeholder workshops; and, as part of the NOAA Harmful Algal Bloom Forecast System, is preparing demonstration forecasts for the Great Lakes. The M&FS will be capable of accepting data, creating models, and transferring results and data to public health, and wa ter management agencies.