Skip to content
Surfhog home
Menu

Cap Ferret wave buoy daily means for Aug 2021

Daily means from the Cap Ferret wave buoy for Aug 2021, including available wave height, period, direction, wind and sea temperature data.

Last observation shown

Data available:  to 

Monthly means for

Latest

Period Summary

Programmatically generated summary. Hog Says

1,488 wave-buoy observations covered all 31 days. Typical wave height was 3 ft (10th–90th percentile 1.9–6.8 ft), while mean peak wave period was 7.7 seconds (10th–90th percentile 4.2–10.7 seconds). Typical calculated wave power was approximately 2.2 kW/m (10th–90th percentile 0.8–16.8 kW/m), derived from significant wave height and energy period. 4 of 4,464 checked values (0.1%) were excluded by quality control. Across 9 comparable years, mean wave height was below the same-month mean of 3.8 ft and mean wave period was below the same-month mean of 8.7 seconds.

Generated only from the observations and comparisons shown on this page.

Typical Significant Wave Height

3ft
Mean: 3.7 ft
P10–P90: 1.9 — 6.8 ft
Recorded extremes

1 — 11.1 ft

Mean Observed Wave Period

7.7secs
P10–P90: 4.2 — 10.7secs
Recorded extremes

3 — 13.6secs

Typical Wave Power

Approximately 2.15kW/m
Mean: 6.21kW/m
P10–P90: 0.84 — 16.76kW/m
Recorded extremes

0.22 — 59.03kW/m

Calculated from significant wave height and energy period.

Typical Observed Wind

-, -mph
Mean: - mph
P10–P90: - — - mph

Available for 0 of 744 hourly samples

Mean Water Temperature

-°C
P10–P90: - — -°C

Available for 0 of 744 hourly samples

Compared With Previous Augusts

Historical baseline from 13,388 observations across 9 years.

Wave Height
3.7ft
0.1ft below mean
Historical mean 3.806ft
Wave Period
7.7s
1s below mean
Historical mean 8.7s
Water Temperature
–
Not enough comparable data

Chart showing grouped wave observations for Cap Ferret. Use the table on this page for a text version of the same measurements. To open hourly observations, use a linked day name in the table.

About Cap Ferret wave buoy

Cap Ferret is a long-running CANDHIS directional buoy off the Aquitaine coast, operated within France's national in-situ sea-state observatory. It provides an offshore reference for the energetic Bay of Biscay swell approaching the Arcachon inlet and the long, sandy and erosion-prone Landes coastline.

Its current data source reports wave height, wave period, wave direction, directional spread and sea temperature.

Metrics are rows; days run left to right.
Cap Ferret wave buoy daily means Aug 2021Last observation shown
Metric
Mean significant wave height (ft)4326598754435546432222332232222
Mean maximum wave height (ft)64310814131186658869744324443344433
Mean peak period (s)88777101191098710111010869868754854479
Mean average period (s)67566998976691078657656554444445
Mean period Tm02 (s)5545577675557756545445444443344
Mean peak wave directionWNWconcentration 100%WNWconcentration 100%WNWconcentration 100%Wconcentration 93%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 89%NWconcentration 96%WNWconcentration 98%WNWconcentration 100%WNWconcentration 99%WNWconcentration 100%WNWconcentration 100%NWconcentration 100%NWconcentration 100%NWconcentration 94%NWconcentration 94%WNWconcentration 99%NWconcentration 92%NNWconcentration 100%Nconcentration 98%NWconcentration 89%NNWconcentration 99%Nconcentration 100%Nconcentration 99%NNWconcentration 95%NWconcentration 97%
Mean directional spread (°)22.422.523.420.919.814.917.118.817.520.921.021.716.315.520.918.721.522.420.926.925.422.323.220.518.726.319.316.617.123.125.7
Mean water temperature(°C)-------------------------------

Swipe sideways to see more days.

Wave metric colour key

Colours move through the scale as each number increases. They do not by themselves mean that conditions are good, safe or suitable for you.

Wave & swell height0–40+ ft
Wave & swell period0–22+ s
Wind speed0–75 mph

The displayed numbers remain the source of truth; colour is an additional visual cue.

What does buoy wave power mean?

kW/m means kilowatts of wave power per metre of wave crest. It describes the rate at which the observed sea state carries energy past the buoy.

Unlike the shore-directed forecast value, buoy wave power is the total power at the observation point. It is not projected towards a particular beach and does not predict breaking wave height.

In deep water, wave power can be calculated with:

P is approximately 0.49 times significant wave height squared times wave energy period.

P is power in kW/m, Hs is significant wave height in metres, and Te is wave energy period in seconds.

  • Provider-reported power is used when available.
  • Otherwise, a value is calculated only when both significant height and a genuine energy period are available. The ≈ symbol marks calculated values.
  • A dash is shown instead of substituting peak, Tm02, zero-crossing or other period measurements.
  • Daily and monthly figures use the mean of hourly-normalized observation power values; they are not calculated from mean height and period.

Wave direction, spectrum, water depth and local bathymetry still matter. Wave power is best read alongside height, period and direction rather than as a standalone surf-quality score.

The observation data displayed on this page is from the Cerema CANDHIS coastal wave observatory.

Learn how SurfHog combines, checks and summarizes observations in the data and methodology notes.

› Wave Buoy List