What does the height of the tide mean?

The tide height is the predicted height of the sea at a particular time in the tidal cycle. Tide heights are normally expressed in metres and are measured against a defined vertical reference level, known as a tidal datum.

For example, a tide table might show a high tide at a particular time with a predicted height of 4.8 metres. This means the predicted sea level at high tide is 4.8 metres above the reference level used for that tidal prediction.

Tide height is important because the difference between high and low water can be significant, particularly around parts of the UK coastline with a large tidal range.

When using tide heights, it is important to remember that predicted values can differ from the actual sea level because weather conditions such as wind and atmospheric pressure can affect the height of the tide.