Chart Navigation & Plotting · Tidal Currents — Velocity Sine Pattern
A reversing tidal current reaches its maximum speed approximately:
- AAt the moment of slack water
- BMidway in time between successive slack waters✓ Correct
- CAt high water only
- DAt a fixed clock time each day
Explanation
A reversing current follows roughly a sine curve: it is zero at slack and builds to maximum flood or ebb about midway between slacks, then eases back to the next slack. Table 3 of the Tidal Current Tables interpolates the velocity at intermediate times.
Authority: NOAA Tidal Current Tables; Bowditch
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