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Fjaltring wave buoy daily means for Sep 2021

Daily means from the Fjaltring wave buoy for Sep 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

798 wave-buoy observations covered 20 of 30 days (67%). Typical wave height was 3.8 ft (10th–90th percentile 1–7.1 ft), while mean average of more than one wave period type was 4.9 seconds (10th–90th percentile 3.6–6 seconds). 2 of 2,351 checked values (0.1%) were excluded by quality control. Across 11 comparable years, mean wave height was above the same-month mean of 4 ft and mean wave period was above the same-month mean of 4.8 seconds.

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

Typical Significant Wave Height

3.8ft
Mean: 4.1 ft
P10–P90: 1 — 7.1 ft
Recorded extremes

0.4 — 14.1 ft

Available for 396 of 406 hourly samples

Mean Observed Wave Period

4.9secs
P10–P90: 3.6 — 6secs
Recorded extremes

2.6 — 7.5secs

Available for 405 of 406 hourly samples

Typical Observed Wind

-, -mph
Mean: - mph
P10–P90: - — - mph

Available for 0 of 406 hourly samples

Mean Water Temperature

-°C
P10–P90: - — -°C

Available for 0 of 406 hourly samples

Compared With Previous Septembers

Historical baseline from 15,152 observations across 11 years.

Wave Height
4.1ft
0.1ft above mean
Historical mean 4.003ft
Wave Period
4.9s
0.1s above mean
Historical mean 4.8s
Water Temperature
–
Not enough comparable data

Chart showing grouped wave observations for Fjaltring. 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 Fjaltring wave buoy

Fjaltring is a Danish Coastal Authority directional buoy off the exposed central west coast of Jutland. The authority has maintained a continuous wave-measurement programme here since 1980, creating a key reference for Denmark's most erosion-prone coast and the long-running Lodbjerg–Nymindegab protection works.

Its current data source reports wave height, wave period and wave direction.

Metrics are rows; days run left to right.
Fjaltring wave buoy daily means Sep 2021Last observation shown
Metric
Mean significant wave height (ft)4463111------------145107522446
Mean average wave height (ft)------------------------------
Mean maximum wave height (ft)76114211--------14---26817129447610
Mean average period (s)6555456------------44566654556
Mean zero-crossing period (s)55553334-------19---34565554555
Mean maximum wave period (s)------------------------------
Mean peak wave directionNWconcentration 100%NWconcentration 100%NWconcentration 100%NWconcentration 100%SWconcentration 75%WSWconcentration 77%Wconcentration 76%WNWconcentration 100%-------Sconcentration 100%---WSWconcentration 84%WSWconcentration 80%WNWconcentration 99%Wconcentration 99%WNWconcentration 96%WNWconcentration 97%WNWconcentration 100%Wconcentration 65%WSWconcentration 98%WSWconcentration 98%Wconcentration 97%

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 Danish Coastal Authority wave-measurement network.

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

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