Tidal-stream Atlas

A set of charts showing predicted tidal-current direction and rate at successive stages of a tidal cycle.

Arrows show set and figures commonly give spring and neap rates for hourly intervals before and after a reference port’s high water. Some atlases use different time references, symbols or interpolation methods, so the legend and edition govern their use.

The diagrams generalise flow over an area and may not resolve coastal eddies, depth variation or short-lived effects. Time zone, reference-port prediction, spring-neap interpolation, weather and local observations should be combined when calculating a tidal vector.