Great tides in Half Moon Bay

The upcoming tides in Half Moon Bay worth planning around, ranked from the next 90 days of predictions (October 18, 2026 to January 15, 2027).

Half Moon Bay is a small coastal city in San Mateo County, about 25 miles south of San Francisco along Highway 1. At the north end of its bay, Pillar Point juts into the Pacific and shelters Pillar Point Harbor at Princeton; just north of the point lies the broad reef flat of Fitzgerald Marine Reserve at Moss Beach, one of the most visited intertidal areas on the San Mateo coast. Predictions here come from the gauge inside Pillar Point Harbor.

Lowest low tides

The lowest predicted low tides at Half Moon Bay in the window, by height. The very lowest tides of a season often fall after dark, so the daylight list below is usually the more useful one for a visit.

Daylight low tides

Low tides that fall between sunrise and sunset in Half Moon Bay, ranked by height. A low tide of 1.5 ft (0.46 m) or lower generally exposes much more of the intertidal zone than an ordinary low; at or below 0.0 ft the exposure is at its best.

Highest high tides

The highest predicted high tides at Half Moon Bay in the window, by height. The top of this list is where this season's king tides appear.

Largest tidal ranges

The biggest swings between one tide and the next at Half Moon Bay: the absolute difference in height between consecutive high and low events, with the time the change takes.

How these rankings are calculated

Great Tides downloads the high/low tide predictions published by NOAA CO-OPS for station 9414131 (Pillar Point Harbor) covering October 18, 2026 to January 15, 2027, and ranks the events directly: low tides by predicted height ascending, high tides by predicted height descending, and tidal ranges by the absolute height difference between consecutive events. Daylight is calculated for Half Moon Bay's coordinates (latitude 37.503, longitude -122.482) with a standard solar-position calculation: a low tide counts as a daylight low when its predicted time falls between that day's sunrise and sunset. Quality labels use height thresholds only: at or below 0.0 ft is labelled “Excellent tidepooling” and 0.0 to 1.5 ft “Good tidepooling”. Rankings are relative to this station and this window; heights at different stations use the same MLLW datum name but are local to each station and are not directly interchangeable.

Questions

Where do these predictions come from?

From NOAA CO-OPS, the US agency that operates the national tide-gauge network. The predictions for Half Moon Bay are calculated for the Pillar Point Harbor station (9414131). This page was generated from the same predictions NOAA publishes in its own tide tables.

Why does the station name differ from the place name?

Places and tide stations are not the same thing. A station is a specific gauge or calculation point; Pillar Point Harbor is the station chosen to represent Half Moon Bay. Tide times and heights shift gradually along the coast, so spots a few miles away will see slightly different times.

Are these live water levels?

No. These are astronomical predictions, calculated in advance from the positions of the Moon and Sun. Wind, storms and air pressure push real water levels above or below the prediction, sometimes by a foot or more.

Can I plan a tidepool visit from this page alone?

Treat the prediction as the starting point, not the whole plan: check the local forecast and conditions before you go, and look up any rules for the harbour and reef flats around Pillar Point, at the north end of Half Moon Bay locally. A low prediction tells you when the water will be out; it says nothing by itself about surf, weather or whether a particular spot is safe that day.

Nearby places

Santa Cruz · Port San Luis & Avila Beach · Crescent City

All California places