A method of ocean property forecasting. The method includes generating one of a magnetic field prediction and an electric field prediction between a first observation point and a plurality of uniform ocean cells by generating a vector sum of magnetic field contributions from a plurality of magnetic field vectors and a vector sum of electric field contributions from a plurality of electric field vectors, respectively. The method further includes generating one of a magnetic field forecast and an electric field forecast of the ocean volume at a second observation point in the ocean volume by re-using the magnetic field vectors and electric field vectors and scaling one of the plurality of magnetic field vectors and the plurality of electric field vectors by a plurality of tri-axial equivalent electrical currents with identical geometry to the first observation point.