The National Oceanic and Atmospheric Administration installed a Physical Oceanographic Real Time System (PORTS) in September 1990 to monitor Tampa Bay. Water surface elevation, currents, temperature, salinity, and meteorological information are available at six-minute intervals to the navigation community and other users in Tampa Bay. To complement the PORTS, a nowcast/forecast system is being developed based on the National Ocean Service (NOS) Tampa Bay three-dimensional hydrodynamic model. The Tampa Bay model will be used to provide bay-wide and up river water level, current, and density forecasts throughout the bay. Each day an experimental 24 hour nowcast and 36 hour forecast of water level, currents, salinity, and temperature will be performed. Experimental nowcasts and forecasts will be made driven by: 1) observed (PORTS) and forecasted (National Weather Service (NWS)) Extra-Tropical Storm Surge model) subtidal water level at Clearwater and St. Petersburg, FL, 2) observed streamflow (United States Geological Survey (USGS)) and forecasted streamflow (NWS Southeast River Forecast Center), and 3) analyzed (PORTS meteorological stations) and forecast (NWS North American Mesoscale model) wind and pressure fields.