Waves in Granville Harbour

Hourly wave forecast for 7 days · updated today, Thursday, October 29, at 1:01 pm (GMT+11)

Now · significant height 14 ft

Sea state: Very rough · Douglas 6
Period: 12.1 s · SW
Swell: 14 ft · 10 s
Highest expected: 27 ft

Waves up to 15 ft today

Today the sea at Granville Harbour is very rough: 14 ft waves with a period of 12.1 s from the southwest. The swell, 14 ft at 10 s, comes from the southwest.

Wave height, next 7 days

5.01015 ft 15 ft Now

Significant height: the average of the highest third of the waves, what an observer would estimate by eye. Swell: waves arriving from far away, longer.

The waves you may find today

Most common6.9 ft
Significant14 ft
Highest expected27 ft

One wave in seven is higher than the significant height, and about 3 times a day one reaches 27 ft. Before heading out, expect waves of up to 27 ft.

The Douglas sea state scale

Degree	Name	Wave height
0	Calm (glassy)	0
1	Calm (rippled)	0.0 ft–0.3 ft
2	Smooth	0.3 ft–1.6 ft
3	Slight	1.6 ft–4.1 ft
4	Moderate	4.1 ft–8.2 ft
5	Rough	8.2 ft–13.1 ft
6	Very rough · today	13.1 ft–19.7 ft
7	High	19.7 ft–29.5 ft
8	Very high	29.5 ft–45.9 ft

Waves day by day

Day	Max wave	Sea state	Direction	Max period	Swell	Max wind
Today	15 ft	Very rough	SW	12 s	15 ft SW	12 mph W
Fri 30	13 ft	Rough	SW	12 s	13 ft SW	11 mph NW
Sat 31	7.7 ft	Moderate	WSW	11 s	7.4 ft SW	18 mph NNW
Sun 1	8.0 ft	Moderate	WSW	10 s	7.7 ft SW	11 mph W
Mon 2	11 ft	Rough	SW	13 s	11 ft SW	9 mph WNW
Tue 3	9.9 ft	Rough	SW	12 s	9.9 ft SW	8 mph WNW
Wed 4	7.5 ft	Moderate	WSW	11 s	6.4 ft WSW	14 mph NW

Today, every 3 hours

Time	12:00 am	3:00 am	6:00 am	9:00 am	12:00 pm	3:00 pm	6:00 pm	9:00 pm
Waves	15 ft	15 ft	15 ft	15 ft	14 ft	13 ft	13 ft	13 ft
Period	11.5 s	11.8 s	12.0 s	12.1 s	12.1 s	12.1 s	11.9 s	11.9 s
Direction	SW	SW	SW	SW	SW	SW	SW	SW
Swell	14 ft · 9 s	15 ft · 10 s	15 ft · 10 s	14 ft · 10 s	14 ft · 10 s	13 ft · 10 s	13 ft · 10 s	13 ft · 10 s
Wind (mph)	12 SW	12 SW	11 WSW	10 WSW	11 W	12 W	10 W	6 W

Previous days

The waves over the last 14 days. Tap a day to see it hour by hour.

Day	Max wave	Period	Swell
Wed 28	14 ft SW	11 s	13 ft SW
Tue 27	9.5 ft WSW	10 s	9.2 ft WSW
Mon 26	10 ft WSW	11 s	9.8 ft WSW
Sun 25	9.8 ft WSW	12 s	9.8 ft WSW
Sat 24	12 ft WSW	14 s	12 ft WSW
Fri 23	11 ft WSW	14 s	11 ft WSW
Thu 22	13 ft WSW	15 s	12 ft WSW

Show all 14 days

Day	Max wave	Period	Swell
Wed 21	11 ft WSW	15 s	11 ft WSW
Tue 20	6.9 ft WSW	12 s	6.2 ft WSW
Mon 19	6.9 ft WSW	13 s	6.6 ft WSW
Sun 18	3.9 ft WSW	12 s	3.6 ft SW
Sat 17	4.3 ft SW	13 s	4.3 ft SW
Fri 16	5.9 ft SW	12 s	5.9 ft SW
Thu 15	8.9 ft SW	11 s	8.9 ft SW

These are the models at the start of each day (ECMWF and GFS; waves from Météo-France), not readings from a weather station: there can be differences at specific spots.

Questions about the waves in Granville HarbourQuestions

How are the waves today in Granville Harbour?

Very rough (14 ft with a period of 12.1 s from the southwest). The highest wave to expect is around 27 ft.

Which day will have the biggest waves this week?

Thursday 29, with waves up to 15 ft (very rough).

What is the wave period?

The time, in seconds, between two crests. With long periods (over 10 s) waves come from far away, are cleaner and break harder; with short periods they are wind waves, choppier.

What is significant wave height?

The average of the highest third of the waves. One in seven is higher and, a few times a day, one comes in at almost double: today, about 27 ft.

More about Granville Harbour today

Waves near Granville Harbour

Only places with a different forecast: spots a few miles apart share the same model cell and wouldn't add anything.

Learn more

Waves: Open-Meteo with Météo-France (MFWAM, up to 10 days) and ECMWF WAM, CC BY 4.0; wave grid point 1.2 mi away. Near the shore, the seabed and the shape of the coast change the waves.

Forecast from Open-Meteo (CC BY 4.0) with models from ECMWF, NOAA, Météo-France, DWD, Copernicus Marine and CAMS. Updated at 1:01 pm (local time).

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