Waves in Katsuura

Hourly wave forecast for 7 days · updated today, Thursday, October 29, at 7:04 pm (GMT+9)

Now · significant height 3.6 ft

Sea state: Slight · Douglas 3
Period: 7.2 s · ESE
Swell: 2.3 ft · 7 s
Highest expected: 7.3 ft

Today the sea at Katsuura is slight: 3.6 ft waves with a period of 7.2 s from the east-southeast. The swell, 2.3 ft at 7 s, comes from the east-southeast. Biggest waves: Wednesday 4, with waves up to 7.9 ft (moderate).

Wave height, next 7 days

2.04.06.08.0 ft 7.9 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 common1.8 ft
Significant3.6 ft
Highest expected7.3 ft

One wave in seven is higher than the significant height, and about 3 times a day one reaches 7.3 ft. Before heading out, expect waves of up to 7.3 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 · today	1.6 ft–4.1 ft
4	Moderate · week peak	4.1 ft–8.2 ft
5	Rough	8.2 ft–13.1 ft
6	Very rough	13.1 ft–19.7 ft

Waves day by day

Day	Max wave	Sea state	Direction	Max period	Swell	Max wind
Today	4.0 ft	Slight	ESE	8 s	3.2 ft SE	9 mph NNE
Fri 30	7.5 ft	Moderate	SE	8 s	7.5 ft SE	11 mph SW
Sat 31	7.0 ft	Moderate	SSE	11 s	6.0 ft SE	10 mph WNW
Sun 1	6.7 ft	Moderate	SE	12 s	6.5 ft SE	6 mph NE
Mon 2	7.6 ft	Moderate	SSE	12 s	6.5 ft SSE	14 mph WSW
Tue 3	7.0 ft	Moderate	S	10 s	5.5 ft S	9 mph NNE
Wed 4	7.9 ft	Moderate	ESE	9 s	5.9 ft SSE	13 mph NNE

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	3.9 ft	3.8 ft	3.7 ft	3.9 ft	3.9 ft	3.7 ft	3.5 ft	3.7 ft
Period	7.6 s	7.4 s	7.5 s	7.1 s	7.2 s	7.2 s	7.3 s	7.1 s
Direction	SE	ESE	ESE	ESE	ESE	ESE	ESE	ESE
Swell	2.3 ft · 6 s	2.2 ft · 6 s	2.3 ft · 6 s	2.2 ft · 6 s	2.4 ft · 6 s	2.2 ft · 6 s	2.0 ft · 8 s	3.0 ft · 4 s
Wind (mph)	7 N	6 N	7 N	9 ENE	6 E	2 E	1 WNW	3 WSW

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	4.6 ft SE	8 s	3.3 ft SSW
Tue 27	5.9 ft ESE	8 s	4.9 ft ESE
Mon 26	5.9 ft SE	8 s	4.3 ft SE
Sun 25	6.6 ft S	10 s	5.2 ft SSE
Sat 24	6.2 ft SSE	9 s	4.9 ft SSE
Fri 23	7.2 ft SE	9 s	4.3 ft SSE
Thu 22	8.5 ft SSE	10 s	5.6 ft S

Show all 14 days

Day	Max wave	Period	Swell
Wed 21	8.5 ft S	9 s	4.6 ft SSE
Tue 20	5.2 ft SSE	9 s	4.3 ft SE
Mon 19	3.9 ft SE	8 s	3.6 ft SE
Sun 18	3.9 ft ESE	7 s	3.6 ft ESE
Sat 17	4.9 ft E	9 s	4.3 ft E
Fri 16	4.6 ft E	9 s	4.3 ft ESE
Thu 15	6.2 ft E	9 s	5.9 ft E

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 KatsuuraQuestions

How are the waves today in Katsuura?

Slight (3.6 ft with a period of 7.2 s from the east-southeast). The highest wave to expect is around 7.3 ft.

Which day will have the biggest waves this week?

Wednesday 4, with waves up to 7.9 ft (moderate).

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 7.3 ft.

More about Katsuura today

Waves near Katsuura

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 2.0 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 7:04 pm (local time).

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