A neap tide is a period of moderate tides occurring twice a month, characterized by the smallest difference between high and low water. Occurring during the moon's first and third quarters, the sun and moon are at right angles, causing their gravitational forces to counteract each other, resulting in lower high tides and higher low tides.

Key Aspects of Neap Tides for Sailors:
Reduced Tidal Range: The vertical distance between high and low tide is minimized.

Weaker Tidal Currents: Tidal streams are generally slower, which can be advantageous when traveling against the tide but less helpful when relying on it for speed.

Reduced Harbor Depth: While low tides are higher, high tides are also lower, which may restrict entry to shallow harbors or anchorages for deep-draft vessels.

Occurrence: They happen approximately seven days after a spring tide.

Neap tides are considered "weak" tides compared to "spring" tides, offering more stable, albeit lower, water levels.