The ROMS (Regional Ocean Modeling System) hydrodynamic model is run for a domain that covers the Irish waters in the northeast Atlantic. The model has a mean horizontal resolution of 1.9 km and 40 terrain-following vertical layers. The system produces a best estimate of the ocean state once a week and also a daily 3-day forecast.

Parameters modeled include: ocean temperature and salinity, sea level, and ocean currents.

In addition, two models with a horizontal resolution of 200 - 250m are nested within the larger model to give 3 day forecasts of ocean state for the greater Galway Bay area (Connemara model) and the southwest of Ireland (Bantry Bay model).

The ocean forecasts are generated on a "best endeavors" basis and should not be used for safety critical applications.