Gyre: Tides & Currents

Gyre is a fun, map-based app for seeing what's going on near or on the water — tide predictions for coastlines worldwide, global ocean currents animated right on the map, and a reading for any spot of open water you tap.

The map is the centerpiece — and it's alive. Wind streams across the surface, waves roll through at the real local period and direction, currents flow worldwide, and the Tides layer colors the whole ocean by the state of the tide.

WHAT YOU CAN DO • Tap to read — turn on Wind, Waves, Currents, or Tides, then tap open water. A dot and a small callout read that layer at the spot you tapped. With Tides on, it shows the tide there: the prediction from the nearest tide station, or, out in open water, a model estimate (an estimate, not a measurement). • Tides layer — the ocean colored by the state of the tide, with tide station markers on the same colors. • Tides — the water level right now, not just the next high and low. Computed on your device from published harmonic constituents, so you can jump to any day, past or future. Charts, high/low times, and a 7-day forecast for thousands of stations, from Puget Sound to Tokyo Bay, the English Channel, and New Zealand. • Currents — worldwide ocean currents animated on the map, modeled by the E.U. Copernicus Marine Service. Speed and direction predictions at NOAA current stations (US), computed the same way as tides. • Weather — current conditions, hourly forecast, marine-zone forecasts, and marine-warning alerts with optional notifications. • Wind & waves — animated overlays you can actually enjoy watching. • Buoys — live offshore observations from NOAA buoys, right on the map. • Astronomy — sun and moon rise/set, phase, and altitude charts. • Search — jump to a station, a buoy, a beach, a surf break, or a harbor. • Widgets — the next tide on your home screen, per-widget station choice.

WHERE THE DATA COMES FROM • Tides: thousands of harmonic stations worldwide, each with its own local time and its own chart datum. • Tide estimates away from stations, and the Tides layer: the FES2022b ocean tide model (LEGOS, NOVELTIS, CLS; funded by CNES; distributed by AVISO+), adjusted to nearby tide gauges. • Currents: worldwide surface currents from the E.U. Copernicus Marine Service; NOAA current stations (US). • Buoys and marine-zone forecasts and warnings: United States (NOAA). • Weather, wind, and waves: worldwide.

BUILT TO BE PLEASANT • No signal needed for station tides — predictions are computed on your device, not fetched. (Map tiles, weather, buoys, the map overlays, and the tide at a tapped spot still need a connection.) • Light, Dark, and System appearance. • Your units, everywhere: distance, wind, temperature, tide height, pressure, and time format. • Accessible: VoiceOver, Dynamic Type, and reduced motion. • Private by design: no accounts, no ads, no tracking, and anonymous usage stats you can switch off.

Gyre is for information and enjoyment only — it is NOT a navigation tool and no substitute for professional marine navigation. It's for the joy of watching the water.