The operational IBI (Iberian Biscay Irish) Ocean Analysis and Forecasting system, daily run by Puertos del Estado and Mercator Ocean, provides a 5-day hydrodynamic forecast (+ 1 day of hindcast as best estimate) including high frequency processes of paramount importance to characterize regional scale marine processes (i.e. tidal forcing, surges and high frequency atmospheric forcing, fresh water river discharge, etc.). The system is based on a (eddy-resolving) NEMO model application run at 1/36 deg. horizontal resolution.