Reading Tidal Current Information on a Garmin® Marine Device

Tidal current is the speed and direction in which water is moving in order to create high or low tides. Garmin® marine chartplotters have the ability to display both a chart and a report indicating the speed and direction of the current.

Here are some general terms used when referring to currents:

• Set - The direction that the current flows toward. Note that this is the opposite of the way winds are reported

• Drift - This is the speed of a current

• Velocity - As the typical term in physics infers, this is an indication of both speed and direction (set and drift)

• Speed - How fast the water is moving in relation to a stationary object (shore, lighthouse)

• Flood Flow - The tidal current is in flood when it is coming from the sea to the shore (tide is coming in, or high tide is ensuing)

• Ebb Flow - The tidal current is in ebb when it is coming from shore and returning to the sea (low tide ensuing)

• Slack Water - The point between flood and ebb (or ebb and flood) currents when there is no horizontal movement

• Stand - The point where vertical changes stop as the tide reverses. This is not the same as slack water; this is a tidal (vertical) occurrence, not a tidal current (horizontal) occurrence

• Maximum Current - The normal maximum speeds of the ebb and flood currents. This does not include effects of weather or run-off from the rain or melting snow, which can significantly affect tidal currents

Knowing the above terms may help with reading the current charts and reports on the devices. Below are screenshots of the current chart and report pages provided by our BlueChart® g3 mapping on a marine device.