Half Moon Bay - 24NM SSW of San Francisco, CA
California, United States
Last wave reading:
Now at the buoy
Significant wave height at the buoy
8.5 ft
2.6 m
- Dominant period
- 14 s
- Direction
- no direction
This reading came without the swell and wind-wave split, so the numbers are for the whole sea.
Long-period groundswell: 8.5 ft at 14 s. Holding steady over the last 6 hours.
Significant wave height is the average of the biggest third of waves at the buoy. It is not surf height at a beach.
Trend at the buoy
Height at the buoy
- Total (significant height)
Period
- Dominant period
Hourly means of the buoy's readings. Arrows point the way the waves travel.
Model vs the buoy
- Buoy, hourly
- Model, past days
- Model forecast
Over the last 5 days, the model ran 29% high against the buoy.
| Day | Height | Peak period | From |
|---|---|---|---|
| Fri, Nov 13 | 20.7 ft | 18 s | WNW |
| Sat, Nov 14 | 25.9 ft | 18 s | WNW |
| Sun, Nov 15 | 17.7 ft | 16 s | WNW |
| Mon, Nov 16 | 18.4 ft | 16 s | WNW |
| Tue, Nov 17 | 15.6 ft | 15 s | WNW |
| Wed, Nov 18 | 10.5 ft | 12 s | W |
| Thu, Nov 19 | 11.4 ft | 12 s | NW |
ECMWF WAM wave model via Open-Meteo, nearest model cell (37.250°N, 123.000°W). Both lines are significant wave height at sea, the same measure the buoy reports. Model output, not a Quiver beach forecast.
Nearby beaches
Listed by distance only. Their Quiver forecasts are not linked to this buoy.
- Mavericks37 km
Quiver forecast now: 9-10ft
Quiver forecast now: 6-7ft
Quiver forecast now: 8-9ft
- Pacifica / Linda Mar43 km
Quiver forecast now: 9-10ft
- Sharp Park Beach46 km
Quiver forecast now: 9-10ft
Beach numbers are each beach's own Quiver forecast, not a conversion of this buoy reading.
Nearby buoys
- San Francisco - 18NM West of San Francisco, CA12.1 ft · 16 sLive · 44 km
- San Francisco Bar, CA10.2 ft · 17 sLive · 53 km
- Monterey - 27NM WNW of Monterey, CA11.2 ft · 16 sLive · 76 km
- Point Reyes, CA11.5 ft · 14 sLive · 83 km
- Bodega Bay - 48NM NW of San Francisco, CA12.1 ft · 15 sLive · 105 km
- Monterey Canyon Outer, CA8.2 ft · 15 sLive · 106 km
Nearest tide station: Pillar Point Harbor, Half Moon Bay 39 km for today’s highs and lows.
Other readings
- Water temperature
- 67°F (19.4°C)
- Wind
- 19 kt from the S, gusts 23 kt
- Air temperature
- 65°F (18.3°C)
- Pressure
- 1006.3 hPa
Reported Nov 12, 11:00 PM GMT-8.
How to read this buoy
Half Moon Bay - 24NM SSW of San Francisco, CA sits 37 km from the closest beach listed here: near enough to show what is arriving, far enough that islands, points and the seabed still change it before it breaks.
Biggest hourly reading in that record: 13.8 ft at 16 s on Nov 8.
- Station id
- 46012
- Operator
- NDBC
- Program
- NDBC Meteorological/Ocean
- Position
- 37.356°N, 122.881°W
- Type
- usv
- Local time zone
- GMT-8 (open ocean)
- Swell split
- Yes, swell and wind waves reported
Source: NOAA National Data Buoy Center (NDBC). Licence: Public domain (US government work). Station page at the source.
Not for navigation. Readings can be late, missing or wrong; check official marine forecasts before going to sea.
Buoy terms
- Significant height
- The average of the biggest third of waves the buoy measured. Sets in the surf zone can be bigger or smaller.
- Dominant period
- Seconds between the waves carrying the most energy. Longer period means more power and more bend around points.
- Swell vs wind waves
- Swell was made by distant wind; wind waves were made nearby. The buoy splits its spectrum at a cutoff period to report each.
- Direction
- Where waves come from, in degrees true. 270° is from the west.
