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Penarth wave buoy observations on Tue, Aug 18, 2026

Hourly readings from the Penarth wave buoy for Tue, Aug 18, 2026, including available wave height, period, direction, wind and sea temperature data.

Last observation shown

Oldest observation available

Daily means for

Latest

Period Summary

Programmatically generated summary. Hog Says

108 wave-buoy observations were recorded during the day. Typical wave height was 1 ft (10th–90th percentile 0.9–1.2 ft), while mean peak wave period was 4.8 seconds (10th–90th percentile 3.8–5.8 seconds). All 216 checked values passed quality control.

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

Line chart showing wave height, wave period and sea temperature for Penarth. Use the detailed observations table below for the same data in text form.

About Penarth wave buoy

Penarth is a Channel Coastal Observatory non-directional wave station in the upper Bristol Channel off the Vale of Glamorgan. Its ten-minute record captures the short-period sea state near Cardiff Bay and Penarth in shallow, strongly tidal waters with a restricted Atlantic fetch.

Its current data source reports wave height and wave period.

Metrics are rows; hours run left to right. Times use your device time zone.
Penarth wave buoy hourly observations Tue, Aug 18, 2026Last observation shown
Metric
Significant wave height (ft)-----------111111111111-------------1111111111111111111111111111111111111111111111111111111111111------------11111111111111111111111111111111111
Maximum wave height (ft)-----------111111111111-------------1111111122222222222222222222222222222211111111111112222222122------------11111111222222222222222222222222221
Peak period (s)-----------666666666666-------------3555555555455333436666633434434444455566665556666666666665655------------35444555555534444446664444444444444
Zero-crossing period (s)-----------444444444444-------------4444444444444444444444444444444444444444444444444444444444444------------44444444444444444444444444444444444

Swipe sideways to see more hours.

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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