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Happisburgh wave buoy daily means for May 2021

Daily means from the Happisburgh wave buoy for May 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 1.7 ft (10th–90th percentile 1–3.2 ft), while mean average of more than one wave period type was 7.2 seconds (10th–90th percentile 4.2–10.3 seconds). Mean water temperature was 11.1°C (10th–90th percentile 9.5–12.2°C). 7 of 5,914 checked values (0.1%) were excluded by quality control. Across 9 comparable years, mean wave height was below the same-month mean of 2.2 ft and mean wave period was above the same-month mean of 6.3 seconds.

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

Typical Significant Wave Height

1.7ft
Mean: 1.9 ft
P10–P90: 1 — 3.2 ft
Recorded extremes

0.5 — 6.6 ft

Mean Observed Wave Period

7.2secs
P10–P90: 4.2 — 10.3secs
Recorded extremes

1.7 — 12.5secs

Observed Wave Direction

NNE

Circular concentration: 83%

Mean Water Temperature

11.1°C
P10–P90: 9.5 — 12.2°C
Recorded extremes

9.3 — 13.6°C

Compared With Previous Mays

Historical baseline from 10,812 observations across 9 years.

Wave Height
1.9ft
0.3ft below mean
Historical mean 2.198ft
Wave Period
7.2s
0.9s above mean
Historical mean 6.3s
Water Temperature
11.1°C
1°C below mean
Historical mean 12.1°C

Chart showing grouped wave observations for Happisburgh. 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 Happisburgh wave buoy

Happisburgh is a Channel Coastal Observatory wave station off the northeast Norfolk coast. It supplies a nearshore North Sea record for one of England's most rapidly changing soft-cliff frontages, where communities, beaches and coastal defences are exposed to frequent erosion.

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

Metrics are rows; days run left to right.
Happisburgh wave buoy daily means May 2021Last observation shown
Metric
Mean significant wave height (ft)221353221111222211122QC rejected211232122
Mean peak period (s)6667998645798799101010897866578864
Mean zero-crossing period (s)4444664433443445444445543455433
Mean peak wave directionNNEconcentration 97%NNEconcentration 99%NEconcentration 75%Nconcentration 69%NNEconcentration 99%NNEconcentration 99%Nconcentration 97%ENEconcentration 74%Econcentration 98%Econcentration 72%NEconcentration 75%NNEconcentration 91%NNEconcentration 90%NNEconcentration 91%NNEconcentration 89%Nconcentration 99%NNEconcentration 99%NNEconcentration 99%NNEconcentration 99%NNEconcentration 70%ENEconcentration 85%Nconcentration 91%NNEconcentration 96%Econcentration 97%Nconcentration 95%Nconcentration 94%NNEconcentration 98%NNEconcentration 98%NNEconcentration 99%NEconcentration 96%NEconcentration 97%
Mean directional spread (°)28.526.130.522.119.623.423.624.131.632.837.132.831.925.828.527.330.130.030.926.531.323.625.827.134.026.923.127.127.831.032.1
Mean water temperature(°C)9.79.79.89.69.49.49.49.59.810.210.610.911.111.311.411.511.611.811.912.011.811.811.711.811.811.811.912.112.412.713.0

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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