Tides, Currents, Wind & Sun

Pelorus Nav overlays predicted conditions directly on the chart, and lets you scrub them up to 48 hours into the future. The tide and current overlays are enabled in Settings → Charts & Layers (off by default); sun times are always a tap away.

Tides & currents

Turn on the Tides & Currents layer group and zoom into a harbor:

• Tide stations show the predicted water height with a trend arrow — 6ft ↑ means six feet and rising. The icon fills with the tide: nearly empty at low water, full at high.
• Current stations draw an arrow pointing the direction the current sets, its length scaled by strength, with the drift labeled as you zoom in (e.g. 0.5 Kt). At slack, a pair of hollow arrows points out the flood and ebb directions instead.

Predictions are computed on the device from NOAA harmonic data bundled with the app, so they work fully offline — no network signal required.

Tap any station for its schedule:

The panel shows conditions right now, then the coming day's events — highs and lows for tide stations; max flood, slack, and max ebb for current stations. Secondary stations (predicted by offsets from a nearby reference station) are labeled as such and are approximate.

The time bar

The chart normally shows conditions now. Tap TIME and a bar appears at the bottom of the chart: drag the slider (or step ±1h) to any point in the next 48 hours, and every prediction overlay — tide heights, current arrows, wind barbs — updates to show that moment. The readout shows the offset and wall-clock time (+3h · Wed 06:18 PM EDT).

Answer questions like "which way will the current be running in the canal at 5 o'clock?" before you commit to it. Now (or closing the bar) snaps back to live conditions; your vessel and GPS always stay in real time.

Wind

The Wind layer group draws standard meteorological wind barbs over the chart — the staff points from the direction the wind is coming from (so the arrow "flies with the wind"); a half barb is 5 knots, a full barb 10, a pennant 50. This barb is 15 knots out of the south — a full barb plus a half barb, with the staff trailing toward the wind's source:

Forecasts come from Open-Meteo, so this overlay needs an internet connection (it fetches a 3-day forecast at a time, and the time bar scrubs within it without re-fetching). A status chip tells you when wind data isn't available.

Sun & twilight times

Tap SUN for a week of dawn, sunrise, sunset, and dusk times at the chart's location (dawn/dusk are civil twilight — roughly when you can still see to work on deck):

Computed offline, like the tides — handy for planning a dawn departure or making sure you clear the harbor entrance before dark.