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Ch. Lightship wave buoy daily means for Apr 2021

Daily means from the Ch. Lightship wave buoy for Apr 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

713 wave-buoy observations covered all 30 days. Typical wave height was 2 ft (10th–90th percentile 0.7–5.2 ft), while mean reported wave period; measurement type unavailable was 6.6 seconds (10th–90th percentile 5–9 seconds). Typical wind was 16.1 mph (10th–90th percentile 6.9–31.1 mph) and mean water temperature was 10°C (10th–90th percentile 9.5–10.4°C). 14 of 3,565 checked values (0.4%) were excluded by quality control. Across 11 comparable years, mean wave height was below the same-month mean of 3.7 ft and mean wave period was below the same-month mean of 7.8 seconds.

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

Typical Wave Height

2ft
Mean: 2.5 ft
P10–P90: 0.7 — 5.2 ft
Recorded extremes

0.3 — 10.2 ft

Available for 710 of 713 hourly samples

Mean Wave Period

6.6secs
P10–P90: 5 — 9secs
Recorded extremes

4 — 11secs

Available for 711 of 713 hourly samples

Mean Water Temperature

10°C
P10–P90: 9.5 — 10.4°C
Recorded extremes

9.2 — 10.9°C

Typical Wind

NE, 16.1mph
Mean: 17.4 mph
P10–P90: 6.9 — 31.1 mph
Recorded extremes

0 — 38 mph

Circular concentration: 53%

Available for 704 of 713 hourly samples

Compared With Previous Aprils

Historical baseline from 7,852 observations across 11 years.

Wave Height
2.5ft
1.2ft below mean
Historical mean 3.7ft
Wave Period
6.6s
1.2s below mean
Historical mean 7.8s
Water Temperature
10°C
0.3°C below mean
Historical mean 10.3°C

Chart showing grouped wave observations for Ch. Lightship. 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 Ch. Lightship wave buoy

Channel Lightship (WMO 62103) is a UK Met Office station in the central English Channel. Its offshore position provides marine observations away from the immediate influence of the coast and is useful for tracking conditions along this major shipping route. The feed can include wind, pressure, air and sea temperature, visibility and wave observations when available.

Metrics are rows; days run left to right.
Ch. Lightship wave buoy daily means Apr 2021Last observation shown
Metric
Mean wave height (ft)354223211122112112222555862121
Mean observed period(s)8Reported7Reported6Reported6Reported5Reported5Reported5Reported6Reported7Reported6Reported5Reported5Reported6Reported7Reported7Reported7Reported7Reported9Reported9Reported9Reported8Reported6Reported6Reported6Reported7Reported7Reported6Reported5Reported6Reported7Reported
Mean wave power(kW/m)------------------------------
Mean wind directionENEconcentration 99%ENEconcentration 98%NEconcentration 95%Nconcentration 46%NNWconcentration 83%NNWconcentration 96%NNWconcentration 71%WSWconcentration 57%Wconcentration 89%NNEconcentration 91%Nconcentration 73%WNWconcentration 91%Econcentration 52%ENEconcentration 91%ENEconcentration 91%NEconcentration 97%NEconcentration 63%NWconcentration 76%Econcentration 92%ENEconcentration 91%ENEconcentration 97%ENEconcentration 99%Econcentration 99%ENEconcentration 99%ENEconcentration 96%ENEconcentration 96%Variableconcentration 16%NNWconcentration 90%Nconcentration 58%NNEconcentration 54%
Mean wind speed (mph)2330221324251671016181998161410811111930292934251016148
Mean water temperature(°C)10.210.19.910.010.09.59.59.89.79.79.69.69.89.99.89.89.810.110.210.310.310.010.010.010.09.910.210.210.310.4

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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.

Which wave period is shown?

The table shows the best period measurement supplied for each observation. It is not necessarily the energy period used to calculate wave power.

Tp
Peak period: the period at the strongest spectral peak.
Tavg
The provider's average wave period.
Tm02
A mean period calculated from the wave spectrum.
Tz
Mean zero-crossing period.
Reported
A legacy value whose period type was not recorded.
Mixed
A daily or monthly mean containing more than one period type.

Wave power needs a genuine energy period (Te). SurfHog does not substitute Tp, Tavg, Tm02 or Tz when Te is missing.

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 UK Met Office.

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