TidePlanet

Waves in Achill Sound

Hourly wave forecast for 7 days · updated today, Thursday, October 29, at 7:20 am (GMT)
Now · significant height 4.8 ft
Sea state
Moderate · Douglas 4
Period
7.4 s · SW
Swell
4.1 ft · 7 s
Highest expected
9.8 ft

Today the sea at Achill Sound is moderate: 4.8 ft waves with a period of 7.4 s from the southwest. The swell, 4.1 ft at 7 s, comes from the west-southwest. Biggest waves: Friday 30, with waves up to 5.8 ft (moderate).

Wave height, next 7 days

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 common2.4 ft
  • Significant4.8 ft
  • Highest expected9.8 ft

One wave in seven is higher than the significant height, and about 3 times a day one reaches 9.8 ft. Before heading out, expect waves of up to 9.8 ft.

The Douglas sea state scale

DegreeNameWave 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 · today 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 5.3 ft Moderate SW 8 s 4.3 ft WSW 21 mph SSE
Fri 30 5.8 ft Moderate SW 11 s 4.7 ft WSW 21 mph SE
Sat 31 4.6 ft Moderate W 11 s 4.3 ft W 7 mph N
Sun 1 3.7 ft Slight W 11 s 3.6 ft W 6 mph NE
Mon 2 2.6 ft Slight W 10 s 2.5 ft W 10 mph ESE
Tue 3 3.3 ft Slight W 14 s 3.3 ft W 7 mph ESE
Wed 4 3.7 ft Slight W 14 s 3.7 ft W 8 mph ESE

Today, every 3 hours

Time 12:00 am3:00 am6:00 am9:00 am12:00 pm3:00 pm6:00 pm9:00 pm
Waves 5.1 ft5.0 ft4.8 ft4.9 ft4.8 ft5.1 ft5.1 ft5.2 ft
Period 7.5 s7.4 s7.5 s7.4 s7.6 s7.6 s7.9 s8.3 s
Direction WSWSWSWSWSWSWSWSW
Swell 4.1 ft · 8 s3.8 ft · 8 s4.2 ft · 7 s4.1 ft · 7 s4.0 ft · 8 s3.9 ft · 8 s3.3 ft · 10 s4.3 ft · 9 s
Wind (mph) 17 S17 S17 SSE17 SSE19 SSE21 SSE20 SSE19 SE

Previous days

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

DayMax wavePeriodSwell
Wed 28 8.2 ft WSW11 s7.2 ft W
Tue 27 11 ft W12 s9.8 ft W
Mon 26 7.5 ft SW11 s6.9 ft W
Sun 25 19 ft W14 s13 ft W
Sat 24 19 ft W13 s6.6 ft WNW
Fri 23 7.5 ft W11 s6.6 ft W
Thu 22 6.6 ft W12 s6.6 ft W
Show all 14 days
DayMax wavePeriodSwell
Wed 21 7.2 ft WNW12 s6.2 ft W
Tue 20 8.9 ft W13 s7.5 ft W
Mon 19 5.9 ft W15 s5.9 ft W
Sun 18 3.6 ft W10 s3.0 ft W
Sat 17 4.3 ft W11 s4.3 ft W
Fri 16 6.9 ft W11 s6.6 ft W
Thu 15 9.2 ft W14 s8.9 ft W

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 Achill SoundQuestions

How are the waves today in Achill Sound?

Moderate (4.8 ft with a period of 7.4 s from the southwest). The highest wave to expect is around 9.8 ft.

Which day will have the biggest waves this week?

Friday 30, with waves up to 5.8 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 9.8 ft.

More about Achill Sound today

Waves near Achill Sound

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 2.2 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 7:20 am (local time).

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