Plymouth Sound

Plymouth Sound is a deep inlet in the English Channel near Plymouth, UK and has been described as one of the world’s greatest natural harbours. Marine water enters the Sound from the south and a deep-water channel runs to the west of the breakwater. Freshwater enters the Sound in the northwest from the River Tamar and the northeast from the River Plym. At the southeast corner of the Sound is Penlee Point on Rame Head in Cornwall and in the southwest is Wembury Point in Devon. Plymouth Hoe forms the northern boundary of the Sound.

There is a wide variety of users of the Sound from naval vessels, cross-channel ferries, and fishing boats to small leisure craft. It has a mile-long breakwater providing a harbour to protect anchored ships from south-western storms.

The table below summarises our forecasts of today’s and tomorrow’s surface ocean and atmospheric conditions.

Line plots

Line plots show the tidal height, water speed and direction for yesterday, today and tomorrow. Hover your mouse over the lines to see the heights at specific times.

Contour plots

Contour plots show how the water speed, temperature and salinity vary with depth over a 72 hour period.

contour plots for Bovisand


Animations show the changes in surface salinity and temperature over a 72 hour period. Lower salinity waters entering from the estuaries and the effects of tides can clearly be seen.