How To Choose A Tide Station

NOAA predictions belong to an identified station coordinate and vertical datum. The station name may mention a city, harbor, pier, or water body, but the prediction does not automatically apply to every shoreline that shares that name. This is why TideAhead displays the station ID and map point instead of presenting a regional tide as a generic city value.

A TideAhead coastal-place page keeps two identities separate. Census or GNIS supplies the place name and representative coordinate; NOAA supplies the tide station. The page names both points and reports the distance between them. Weather and astronomy are requested for the place coordinate, while the tide remains attributed to its station.

TideAhead ranks nearby stations with the Haversine formula, using latitude and longitude on a spherical Earth with a radius of 3,958.8 miles. The calculation follows the Earth's surface and handles longitude correctly; it is not a flat map's straight-line pixel distance. Results shown to visitors are rounded to one decimal mile.

A place page is available only when a current NOAA tide-prediction station is within 30 geodesic miles. That threshold is a coverage boundary, not a scientific statement that every station inside the radius is equivalent. TideAhead does not spatially interpolate a new tide at the place coordinate.

The most important visual question is whether the destination and station share the same connected coastal setting. Look for headlands, river mouths, narrow channels, lagoon entrances, barrier islands, islands, locks, and long estuary branches. Those features can affect timing, range, and the relationship between water level and current.

A station farther away along the same bay or open coast may sometimes be more informative than a closer station across land or in a different inlet. TideAhead's nearby-station map makes comparison easier, but local harbor guidance, park information, and experience remain important when small timing differences matter.

A NOAA reference station supports a complete harmonic prediction series. A subordinate station applies official time and height relationships to a reference station and may publish only high and low events through the NOAA API. A subordinate station can be locally useful even though its TideAhead chart contains fewer official points.

Prefer the station that best represents the destination, not simply the one with the smoothest chart. If you use a subordinate station, pay close attention to the official extrema and the dashed derived segments. If you need a continuous official prediction for comparison, open the named reference station as well.

1. Search the exact destination and open the selected place or station on the map.
2. Confirm station name, NOAA ID, state or territory, coordinate, and disclosed distance.
3. Compare other nearby NOAA stations that share the same bay, inlet, estuary branch, or open coast.
4. Check whether the page uses a reference or subordinate station and whether the needed prediction detail is available.
5. When timing is safety-critical or access-specific, verify with the managing agency, harbor, guide, or official local publication.

• A nearby NOAA station is not proof of public shoreline access, parking, boat launching, or legal fishing access.
• Distance does not establish that water depth, current, waves, or breaking surf match the station.
• A tide-prediction station is not necessarily an active weather or water-temperature sensor.
• A city coordinate is usually a representative mapping point, not the exact beach, ramp, or pier a visitor intends to use.
• An official prediction does not replace closure notices, navigation charts, or real-time warnings.

Start on TideAhead's national NOAA station map and compare nearby stations. The authoritative station record and predictions are available through NOAA Tides & Currents. After choosing a station, use the tide-chart reading guide to evaluate the full arrival and departure window.