Tidal Stream predictions are provided for Port Phillip Heads, Victoria and Torres Strait, Queensland. This service provides the time and speed of the maximum stream flow and the time of slack water.
The predictions are for seven days. You can select the start of the seven days up to 2 years ahead.
The predictions are in daylight saving time when it is observed.
A tidal stream is the periodic movement of water in a horizontal direction that is due to the same astronomical causes as the tide (the tide is a movement in the vertical direction). In general, as the tides rise there will be a current flowing from the oceans into the bays, harbours and estuaries; this is termed a "flood stream". As the tides fall there will be a current flowing towards the oceans; this is termed an "ebb stream". Between the two there are periods when there is little or no flow; this is called "slack water".
The following information about tidal stream predictions for both Port Phillip Heads and Torres Strait is based on the Australian Seafarers Handbook (chapter 3), published by the Australian Hydrographic Service.