W Arch
The Okinose W-Arch is located on the easternmost tip of Toyama Prefecture in Japan, specifically on the Etchu-Miyazaki Coast. Situated approximately 1 kilometer offshore, this dive site faces the open ocean, providing divers with a unique underwater experience. The water remains clear from spring through summer, although occasional strong currents can be encountered. With a depth of around 15 meters, this site is exceptionally rare due to the presence of two arches side by side, a phenomenon seldom found on the Sea of Japan side. Local folklore suggests that an ancient shrine once existed in this area, giving it a reputation as a power spot. Visiting this site is highly recommended for divers.
At the Okinose W-Arch, divers can expect to encounter a diverse range of marine life. From big snappers and amberjack to yellowtail, sunfish, peppers, kijihata, aohata, and horse mackerel, the variety of species is impressive. Additionally, the ecosystem here includes snappers, minnows, red snappers, Kerama snapper, yellowtail, yellow-bellied nudibranch, white nudibranchs, Sagami nudibranchs, and sea fans. This dive site offers an abundance of underwater life for divers to observe and enjoy.
To reach the Okinose W-Arch, it requires a short 5-minute boat ride from the harbor. The maximum depth of this site is approximately 30 meters, but divers should be aware that strong currents may occur on certain days. It is recommended that divers have an advanced or expert level of experience. Free dives are common for entry, necessitating precise control of dive speed and neutral buoyancy. With its diverse topographic features, rich marine life, macro photography opportunities, and underwater relics, this dive site is an attractive destination for divers with various interests.
For those planning to visit, the coordinates of the Okinose W-Arch's close location are Miyazaki, Asahi, Shimoniikawa County, Toyama Prefecture, 939-0703, Japan. The visibility generally reaches up to 10 meters, and the maximum depth is around 20 meters.
At the Okinose W-Arch, divers can expect to encounter a diverse range of marine life. From big snappers and amberjack to yellowtail, sunfish, peppers, kijihata, aohata, and horse mackerel, the variety of species is impressive. Additionally, the ecosystem here includes snappers, minnows, red snappers, Kerama snapper, yellowtail, yellow-bellied nudibranch, white nudibranchs, Sagami nudibranchs, and sea fans. This dive site offers an abundance of underwater life for divers to observe and enjoy.
To reach the Okinose W-Arch, it requires a short 5-minute boat ride from the harbor. The maximum depth of this site is approximately 30 meters, but divers should be aware that strong currents may occur on certain days. It is recommended that divers have an advanced or expert level of experience. Free dives are common for entry, necessitating precise control of dive speed and neutral buoyancy. With its diverse topographic features, rich marine life, macro photography opportunities, and underwater relics, this dive site is an attractive destination for divers with various interests.
For those planning to visit, the coordinates of the Okinose W-Arch's close location are Miyazaki, Asahi, Shimoniikawa County, Toyama Prefecture, 939-0703, Japan. The visibility generally reaches up to 10 meters, and the maximum depth is around 20 meters.
Diving Conditions Score for W Arch
8.7
Very GoodVery good diving conditions!
The score is based on a calculation of the current weather and sea conditions.
Dive Site Overview for W Arch
Depth
20m
Visibility
10m
Experience Level
advanced
expert
Weather Conditions for W Arch
Wave Height
0.06m
Wind Speed
3.1 m/s
Water Temp
23.2°C
Visibility
25.46km
Cloud Cover
34%
Wave Period
2.75s
Air Temperature
21.8°C
Precipitation
0 mm
Detailed 7-Day Diving Forecast for W Arch
Alpha
Dive Score Chart for W Arch
Best time to dive: 14:00 with score 9.162745454545455/10. Water conditions: Waves 0.06m, Wind 3.1 m/s.Best night dive time: 2:00 with score 8.874819125683059/10.
Chart showing hourly dive conditions including wave height, wind speed, water temperature, and visibility throughout the day.
Sunrise at W Arch: 06:00
Sunset at W Arch: 18:00
Optimal diving conditions at W Arch are affected by daylight hours. Sunrise occurs at 06:00 and sunset at 18:00, which impacts visibility and water temperature for scuba diving and snorkeling.
Best Overall
14:00Score: 9.2/10
Waves: 0.06m (2.75s), Wind: 3.1 m/s
Best Night
2:00Score: 8.9/10
Waves: 0.06m, Wind: 0.4 m/s
Seasonal Analysis for W ArchAlpha
Historical patterns and best seasons for diving at W Arch
The dive score combines all factors to rate overall diving conditions throughout the year. Higher scores indicate better diving conditions.
Monthly Dive Score Analysis - Seasonal Diving Conditions
Higher values indicate better diving conditions
Seasonal DiveScore Chart
This chart displays monthly diveScore data throughout the year, showing seasonal patterns. The data is presented as a bar chart with an overlaid line graph.Dive scores range from 1 to 10, with 10 being optimal conditions.
Higher values indicate better diving conditions
Best Season for W Arch
Winter
Avg. Score: 7.6/10
Winter offers the best overall diving conditions with calmer seas and better visibility, despite cooler temperatures.
Best Months for W Arch
January
Score: 7.8
February
Score: 7.5
November
Score: 7.4
Ideal Conditions for W Arch
Water Temp
26.2°C / 79.2°F
July
Visibility
12.0m / 39.4ft
May
Wave Height
1.4m / 4.6ft
November
Wave Period
8.0s
January
Seasonal Insights for W Arch
W Arch shows typical northern hemisphere patterns with July being the warmest month (26.2°C) and January the coldest (-1.3°C). The calmest conditions typically occur in November with average wave heights of 1.4m and wave periods of 8.0s. The most comfortable wave conditions are in November with a low wave steepness ratio, creating gentler swells. January offers the longest wave periods (8.0s), creating more comfortable and predictable conditions for boat entries and exits. Ocean currents are slowest in January (0.5m/s) and strongest in January (0.5m/s). May is usually the driest month with 0.0mm of precipitation. For beginners, the best time to visit would be during November to January, when ocean conditions are calmer with long-period waves and currents are typically weaker. Experienced divers might enjoy the challenges and potentially better visibility during the shoulder seasons, with moderate currents that can improve marine life encounters.
Last updated: 1 min. ago - Jun 18, 2026
Note: This dive site is not a verified dive site. Please dive with caution. This dive site might have incorrect information by the community.
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