# neap tides or tidal currents

#### Definition

Tides of decreased range or tidal currents of decreased velocity occurring semi-monthly as the result of the moon being in quadrature (i.e. the sun and the moon acting at right angles to each other). The range of neap tides is the average semidiurnal range occurring at the time of neap tides and is most conveniently computed from the harmonic constants. It is smaller than the mean range where the type of tide is either semidiurnal or mixed and is of no practical significance where the type of tide is diurnal. The average height of the high waters of the neap tide is called neap high water or high water neaps and the average height of the corresponding low waters is called neap low water or low water neaps.