We have developed a regional operational oceanographic system for the coastal waters of Korea. The operational modeling system consists of atmospheric and hydrodynamic models coupled with three-dimensional hydrodynamics, waves, sediment transport and water quality modules. The storm surge and hydrodynamics variables are forecasted in the 72-hours base. The results are exported to the web-GIS system for real-time dissemination for the public. The operational system has been developed for the coastal waters of KoreaWe use the operational model ROMS to analyze the dynamic response of semi-enclosed bays in the coastal waters of Korea from the typhoon KOMPASU. The forcing is coupled with time- and space- varying parameters such as typhoon winds, pressure, waves, tides and buoyant effect due to fresh water from land. The dynamic responses are analyzed in terms of 3 dimensional flow structure and sea surface variation adopting high resolving dry/wet scheme according to the different set of forcing parameters