Spring Tide
D2. Hydrography, tides, waves, bathymetry and marine geologyDefinition
Tide with largest range, near new and full moon.
Spring tides are the tides of greatest range, occurring about twice a month near new and full moon when the Sun and Moon align and their tide-raising forces add (the M2 and S2 constituents in phase). High waters run higher and low waters lower than average. The term has nothing to do with the season; it comes from the water springing up. Perigean spring tides near lunar perigee are larger still.