A coupled ocean data assimilation system developed in NRL Monterey comprises a three-dimensional Multivariate Optimum Interpolation (MVOI) ocean analysis and a hydrostatic ocean forecast model. The ocean model used here is the NRL Coastal Ocean Model (NCOM), which is coupled to the COAMPSTM atmospheric forecast model through one-way interaction. The observations used in the ocean analysis are altimeter, ship, profile, MCSST, and SSM/I data from the Global Ocean Data Assimilation Experiment (GODAE) server at the Fleet Numerical Meteorology and Oceanography Center (FNMOC). This coupled ocean data assimilation system can be relocated to any geographic area by using the 1/8° global NCOM real time nowcast or forecast fields for the initial and lateral boundary conditions for the regional ocean forecast. The daily global NCOM forecast fields update the lateral boundary conditions every 3 hours for a 72-h regional NCOM forecast in the Monterey Bay. The hourly atmospheric forcing fields are generated by a high-resolution COAMPSTM atmospheric forecast using a four-nested grid with the finest grid resolution of 3 km. The ocean model grid spacings are 3 km in the horizontal and they range from 2 to 536 m in vertical (40 levels). The results from this coupled ocean data assimilation system will be compared with the observation data obtained by the Autonomous Ocean Sampling Network II (AOSN II) from August 3 to September 8, 2003 to study upwelling features in the Monterey Bay. To be presented at the Symposium on Forecasting the Weather and Climate of the Atmosphere and Ocean, 11-15 January 2004, Seattle, WA.