Which phase of the moon is associated with spring tides?

Spring tides occur during the new moon and full moon phases. This phenomenon happens because, during these times, the alignment of the Earth, the Moon, and the Sun allows the gravitational forces to combine their effects. When the Moon is positioned directly between the Earth and the Sun (new moon) or on the opposite side of the Earth from the Sun (full moon), the gravitational pull on the oceans is strongest. This causes the tides to rise higher than usual, resulting in what we call "spring tides."

During the waxing gibbous, waning gibbous, and last quarter phases, the gravitational influences of the Sun and Moon are not as effectively aligned, leading to lower high tides and higher low tides. Thus, these phases are not associated with spring tides, as they do not produce the maximum tidal ranges that occur during the new and full moon phases.