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Read GPS speed warnings in restricted zones

GPS speed gauges automatically show yellow as you approach an active speed restriction and red when you reach its limit. This applies to digital, sweeping, linear, and history gauges, including gauges using a specific GPS source.

Show GPS speed​

Use a saved-view gauge with the GPS Speed source, which measures speed over ground. You need a current vessel position and available restriction coverage for that position. A water-speed gauge does not use these zone thresholds.

The zone check works while a GPS speed gauge is visible, including dashboards without a map. No separate warning setting is needed.

Read the colors​

  • Yellow: speed has reached the warning threshold, 0.5 kt below the zone's limit, and is still below the limit.
  • Red: speed is at or above the zone's limit.
  • No wake: BoatKit treats the zone as a 5 kt limit for gauge colors, showing yellow at 4.5 kt and red at 5 kt.

For example, a 6 kt restriction shows yellow from 5.5 kt and red from 6 kt. The thresholds convert to your preferred speed units. Where active zones overlap, the lowest limit applies. Inactive seasonal zones and holes in a zone's polygon do not apply.

These temporary thresholds replace the gauge's upper warning and alert thresholds while you are inside the zone. Any configured lower thresholds remain active. Leaving the zone restores the saved upper thresholds.

Gauge colors are visual warnings only; they do not sound an alarm or send a notification.

Offline use and troubleshooting​

A Viewer connected directly to the vessel can use restriction data already available aboard without an Internet connection. A Viewer connected through BoatKit Cloud needs its cloud connection. Missing coverage does not prevent the gauge from displaying GPS speed.

If the expected zone colors do not appear, check that the gauge uses GPS speed over ground, the vessel position and speed are available, and the restriction is active with coverage available for your location. The numeric speed, rather than its rounded label, determines the color.