We have just pushed live a 3D high res current model for Marseille. It is a 100 metre resolution model that also has a wind driven element to it from the Arome weather model.
The model is 3D in full baroclinic mode. It means that the model will calculate the current velocities using wind and the density difference in the water column (strong temperature and salinity gradient).
The tide influence (moon cycle) is small (0.25m range) so the current is mainly from wind and the density difference in the water column. The model also uses the bathymetry of the harbour in fine detail.
The wind influence can (from Arome model):
Bring upwelling along the coast (cold water from the deeper ocean comes to the surface) and increase temperature difference.
Bring fresher water from the river Rhone into Rade De Marseille
Bring the Northern current (current that flows counterclockwise along the coast of France) or offshore water into the bay.
The update times for the model are 0700 and 1900 UTC and the run length is 36 hours. You need to be looking at the 100 meter resolution, as soon as you flick over to 400m res you are looking at modeling that is not wind driven and coarser resolution (you would be either outside run time or too zoomed out). While on the water the app should be showing your location with a white dot, at the moment this only updates each time you open the app.
Available in PredictWind with a Standard or Pro forecast subscription or PredictCurrent Pro.