Skip to content
Surfhog home
Menu

Cap Ferret wave buoy daily means for Sep 2009

Daily means from the Cap Ferret wave buoy for Sep 2009, 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

1,440 wave-buoy observations covered all 30 days. Typical wave height was 3.8 ft (10th–90th percentile 2.5–7.4 ft), while mean average of more than one wave period type was 9.2 seconds (10th–90th percentile 5.3–11.8 seconds). Typical calculated wave power was approximately 4.6 kW/m (10th–90th percentile 2–19.6 kW/m), derived from significant wave height and energy period. 4 of 4,317 checked values (0.1%) were excluded by quality control.

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

Typical Significant Wave Height

3.8ft
Mean: 4.3 ft
P10–P90: 2.5 — 7.4 ft
Recorded extremes

1.7 — 12.6 ft

Mean Observed Wave Period

9.2secs
P10–P90: 5.3 — 11.8secs
Recorded extremes

4.1 — 14.6secs

Typical Wave Power

Approximately 4.57kW/m
Mean: 8.09kW/m
P10–P90: 2.03 — 19.59kW/m
Recorded extremes

0.93 — 68.31kW/m

Calculated from significant wave height and energy period.

Available for 719 of 720 hourly samples with wave power

Typical Observed Wind

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

Available for 0 of 720 hourly samples

Mean Water Temperature

-°C
P10–P90: - — -°C

Available for 0 of 720 hourly samples

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 and wave period.

Metrics are rows; days run left to right.
Cap Ferret wave buoy daily means Sep 2009Last observation shown
Metric
Mean significant wave height (ft)489963323543343443665455433332
Mean maximum wave height (ft)61215141054357655656759107678654453
Mean average period (s)61098891098965555710767791111778898
Mean peak wave directionWconcentration 95%WNWconcentration 100%WNWconcentration 100%WNWconcentration 99%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%NWconcentration 96%NNWconcentration 99%NNWconcentration 99%NNWconcentration 100%NWconcentration 100%NWconcentration 99%WNWconcentration 100%WNWconcentration 100%WNWconcentration 99%NWconcentration 98%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%WNWconcentration 100%NWconcentration 100%NWconcentration 100%
Mean directional spread (°)25.915.718.321.720.121.618.923.420.118.022.817.416.617.821.720.817.625.429.827.319.119.415.915.420.018.618.318.016.522.8

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.

Observation data source

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

› Wave Buoy List