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Seaford wave buoy monthly means for 2021

Monthly means from the Seaford wave buoy for 2021, including available wave height, period, direction, wind and sea temperature data.

Last observation shown

Data available:  to 

Latest

Period Summary

Programmatically generated summary. Hog Says

8,633 wave-buoy observations covered 363 of 365 days (99%). Typical wave height was 1.4 ft (10th–90th percentile 0.6–5.4 ft), while the reported wave period averaged 3.8 seconds (10th–90th percentile 3–5 seconds). Typical wind was 0 mph and mean water temperature was 12.6°C (10th–90th percentile 7.4–18.6°C). 8 of 43,165 checked values (0%) were excluded by quality control.

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

Typical Significant Wave Height

1.4ft
Mean: 2.3 ft
P10–P90: 0.6 — 5.4 ft
Recorded extremes

0.3 — 13 ft

Available for 8,629 of 8,633 hourly samples

Mean Observed Wave Period

3.8secs
P10–P90: 3 — 5secs
Recorded extremes

2 — 9secs

Available for 8,631 of 8,633 hourly samples

Observed Wave Direction

SSW

Circular concentration: 79%

Mean Water Temperature

12.6°C
P10–P90: 7.4 — 18.6°C
Recorded extremes

4.8 — 25.6°C

Available for 8,631 of 8,633 hourly samples

Chart showing grouped wave observations for Seaford. Use the table on this page for a text version of the same measurements. To open daily observations, use a linked month name in the table.

About Seaford wave buoy

Seaford is a National Network Datawell Directional WaveRider in about 11 metres of water off East Sussex. First deployed on 22 January 2008, it records waves reaching Seaford Bay between Newhaven and Beachy Head and supports assessment of the town's exposed shingle frontage.

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

Metrics are rows; months run left to right.
Seaford wave buoy monthly means 2021Last observation shown
Metric
Mean significant wave height (ft)333131222423
Mean maximum wave height (ft)------------
Mean peak period (s)------------
Mean zero-crossing period (s)------------
Mean energy period (s)------------
Mean reported period (s)444343344444
Mean wave power, kilowatts per metre------------
Mean peak wave direction------------
Mean directional spread (°)------------
Mean reported wave directionSSWconcentration 80%SSWconcentration 80%SSWconcentration 86%Sconcentration 67%SWconcentration 90%SWconcentration 74%SWconcentration 83%SWconcentration 77%SSWconcentration 72%SWconcentration 91%SWconcentration 80%SSWconcentration 83%
Mean water temperature(°C)7.86.87.89.111.615.317.718.618.515.612.79.2

Swipe sideways to see more months.

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 Regional Coastal Monitoring Programme.

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

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