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Seaford wave buoy daily means for Jan 2021

Daily means from the Seaford wave buoy for Jan 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

733 wave-buoy observations covered all 31 days. Typical wave height was 2.2 ft (10th–90th percentile 0.5–7.2 ft), while the reported wave period averaged 4.2 seconds (10th–90th percentile 3–5 seconds). Typical wind was 0 mph and mean water temperature was 7.8°C (10th–90th percentile 7.3–8.5°C). 4 of 3,665 checked values (0.1%) were excluded by quality control. Across 7 comparable years, mean wave height was below the same-month mean of 3.9 ft and mean wave period was below the same-month mean of 7.1 seconds.

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

Typical Significant Wave Height

2.2ft
Mean: 2.9 ft
P10–P90: 0.5 — 7.2 ft
Recorded extremes

0.3 — 12.1 ft

Available for 730 of 733 hourly samples

Mean Observed Wave Period

4.2secs
P10–P90: 3 — 5secs
Recorded extremes

2 — 9secs

Available for 732 of 733 hourly samples

Observed Wave Direction

SSW

Circular concentration: 80%

Mean Water Temperature

7.8°C
P10–P90: 7.3 — 8.5°C
Recorded extremes

6.6 — 9°C

Compared With Previous Januarys

Historical baseline from 4,939 observations across 7 years.

Wave Height
2.9ft
1ft below mean
Historical mean 3.9ft
Wave Period
4.2s
2.9s below mean
Historical mean 7.1s
Water Temperature
7.8°C
0.6°C below mean
Historical mean 8.4°C

Chart showing grouped wave observations for Seaford. 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 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; days run left to right.
Seaford wave buoy daily means Jan 2021Last observation shown
Metric
Mean significant wave height (ft)1111111111453425338QC rejected73332535632
Mean maximum wave height (ft)-------------------------------
Mean peak period (s)-------------------------------
Mean zero-crossing period (s)-------------------------------
Mean energy period (s)-------------------------------
Mean reported period (s)4344343333455554445654554444545
Mean wave power, kilowatts per metre-------------------------------
Mean peak wave direction-------------------------------
Mean directional spread (°)-------------------------------
Mean reported wave directionSWconcentration 90%SWconcentration 86%SSEconcentration 90%SEconcentration 85%SEconcentration 49%SSEconcentration 89%SWconcentration 56%SSWconcentration 80%SSEconcentration 92%SWconcentration 94%WSWconcentration 100%SWconcentration 100%SWconcentration 100%SWconcentration 100%SSWconcentration 90%SSWconcentration 96%SWconcentration 99%SWconcentration 98%SWconcentration 99%SSWconcentration 92%SWconcentration 98%SWconcentration 98%SWconcentration 98%SWconcentration 98%SWconcentration 94%SWconcentration 96%SSWconcentration 79%SWconcentration 100%SWconcentration 100%SSEconcentration 70%SSWconcentration 89%
Mean water temperature(°C)8.78.78.78.68.38.17.87.77.67.57.67.37.57.67.57.47.47.67.57.77.57.27.77.87.97.77.67.87.77.87.7

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 Regional Coastal Monitoring Programme.

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

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