When do maximum currents occur?

The maximum currents occur at the midpoint between high and low tide due to the gravitational forces exerted by the moon and the sun, which create tidal movements. At this midpoint, the water is moving from the high water level to the low water level, generating the strongest flow or current. This is when the tide transitions between its peaks and troughs, leading to the fastest exchange of water.

In contrast, low slack and high slack refer to the periods of calm before the water flows changes direction; therefore, currents are minimal, not maximum. Low tide indicates a point of lower water level but does not specify the flow, as currents have already peaked and are starting to slow down. High tide represents a peak water level but, similarly to low slack, is not when the current is moving at its maximum velocity.

Understanding the phases of the tide and their effect on water movement is crucial for safe navigation and planning in sailing, as strong currents can affect vessel handling and require calculated timing for traversing areas of significant tidal influences.