The U.S. Naval Oceanographic Office (NAVOCEANO) is developing an operational capability to forecast ocean currents and thermal structure in nearshore regions and semienclosed seas. Development thus far has emphasized semienclosed seas because of the relative ease of defining boundary conditions. The first area for which a modeling system was implemented was the Persian Gulf. Operational use of the modeling system for this area began in November 1990, but the modeling system has continued to evolve and undergo additional testing. We have applied the modeling system developed for the Persian Gulf to two other semienclosed basins, the Red Sea and the Mediterranean, and they are being tested for possible operational use.