Wednesday
✅ good conditions
Main blocker: Waves
Kerama Islands Snorkel Report Today
Japan · Updated Tue 04:14 (JST) · Source: Snapshot
The skinny
Go in the best window Report Wed 12:55Kerama Islands has a usable snorkeling window around Wed 13:00. The main thing to watch is waves.
Score: 7.0/10
Best time: Wed 13:00
Main risk: Waves
No useful morning window is showing yet.
Best afternoon signal: Wed 14:00 (Good). Peak afternoon wind is about 2.2 m/s.
Good window is available today
Next safe window: Wed 04:00–10:00 (38% of next 72h are suitable)
3-day planner
Thursday
✅ good conditions
Main blocker: Waves
Friday
⚠️ fair conditions
Main blocker: Waves
Best available hours
Next safe window starts at Wed 04:00 until 10:00.
Why this verdict
Main blockers across the next 72 hours:
- Waves (48 hours)
- Tide/current (43 hours)
- Darkness (26 hours)
Jellyfish drift risk
Drift estimate from wind, swell, current and warm water.
Low peak drift risk around Thu 00:00.
warm water supports seasonal jellyfish activity; surface drift/current is noticeable; local shoreline exposure is not mapped yet.
Sightings override the model: if you see small purple jellyfish with long trailing tentacles, treat them as sting-capable and give them space.
Upcoming high tides
Wed 04:00
Nearby alternatives in Japan
Advanced forecast data
Viewing historical data
Thu 03:00 – Sun 03:00 (JST)
Snorkel Score (selected 24h)
Best snorkel score is 0.31 around Thu 13:00; 0 of 24 hours are good, fair, or excellent.
Score trend, higher is better. Excellent ≥ 0.72, good 0.55–0.72, fair 0.35–0.55.
Conditions (24h trends)
Tap a chart to load just that series.
0/24 sampled hours stay at or below 0.36m (range 3.3m to 5.8m).
Wind is at or below 5.4m/s in 0/24 sampled hours (range 9.28 to 15.12m/s).
Tides range from 0.42m to 1.7m; 2 of 24 hours are in or near peak slack windows.
72-hour historical overview
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Scoring methodology (for technical users)
We score each hour from 0 to 1 using daylight and these weighted components:
- Wave height (35%): best below 0.36m, then decreases as it rises.
- Wind speed (25%): best below 5.4m/s, lower is better.
- Sea surface temperature (15%): best within 20.6°C to 30.4°C.
- Tide and currents (15%): best around slack/high-tide windows.
- Daylight (10%): visibility and safety gate (outside daylight scores lower).
Detailed hourly data table
| Time | Wave (m) | Wind (m/s) | Sea temp (°C) | Status |
|---|---|---|---|---|
| Thu 03:00 | 3.56 · high | 9.28 · high | 28.80 · good | poor |
| Thu 04:00 | 3.62 · high | 9.49 · high | 28.90 · good | poor |
| Thu 05:00 | 3.70 · high | 9.80 · high | 29.00 · good | poor |
| Thu 06:00 | 3.76 · high | 9.95 · high | 29.00 · good | poor |
| Thu 07:00 | 3.84 · high | 10.41 · high | 29.10 · good | poor |
| Thu 08:00 | 3.92 · high | 11.01 · high | 29.10 · good | poor |
| Thu 09:00 | 3.30 · high | 11.06 · high | 29.20 · good | poor |
| Thu 10:00 | 3.40 · high | 11.32 · high | 29.20 · good | poor |
| Thu 11:00 | 3.52 · high | 10.42 · high | 29.20 · good | poor |
| Thu 12:00 | 3.62 · high | 12.50 · high | 29.20 · good | poor |
| Thu 13:00 | 3.70 · high | 11.47 · high | 29.20 · good | poor |
| Thu 14:00 | 3.76 · high | 12.30 · high | 29.20 · good | poor |
| Thu 15:00 | 3.84 · high | 12.02 · high | 29.20 · good | poor |
| Thu 16:00 | 3.96 · high | 10.93 · high | 29.20 · good | poor |
| Thu 17:00 | 4.08 · high | 11.48 · high | 29.10 · good | poor |
| Thu 18:00 | 4.20 · high | 12.24 · high | 29.10 · good | poor |
| Thu 19:00 | 4.40 · high | 13.10 · high | 29.10 · good | poor |
| Thu 20:00 | 4.60 · high | 13.25 · high | 29.10 · good | poor |
| Thu 21:00 | 4.80 · high | 13.57 · high | 29.10 · good | poor |
| Thu 22:00 | 5.00 · high | 14.88 · high | 29.00 · good | poor |
| Thu 23:00 | 5.20 · high | 13.69 · high | 29.00 · good | poor |
| Fri 00:00 | 5.40 · high | 15.12 · high | 29.00 · good | poor |
| Fri 01:00 | 5.60 · high | 15.09 · high | 28.90 · good | poor |
| Fri 02:00 | 5.80 · high | 14.87 · high | 28.90 · good | poor |
| Fri 03:00 | 6.00 · high | 16.56 · high | 28.80 · good | poor |
| Fri 04:00 | 6.10 · high | 18.66 · high | 28.70 · good | poor |
| Fri 05:00 | 6.22 · high | 20.10 · high | 28.70 · good | poor |
| Fri 06:00 | 6.32 · high | 17.87 · high | 28.60 · good | poor |
| Fri 07:00 | 6.56 · high | 20.86 · high | 28.60 · good | poor |
| Fri 08:00 | 6.80 · high | 19.55 · high | 28.50 · good | poor |
| Fri 09:00 | 7.04 · high | 19.12 · high | 28.50 · good | poor |
| Fri 10:00 | 7.14 · high | 19.40 · high | 28.40 · good | poor |
| Fri 11:00 | 7.22 · high | 22.14 · high | 28.40 · good | poor |
| Fri 12:00 | 7.32 · high | 23.20 · high | 28.30 · good | poor |
| Fri 13:00 | 7.30 · high | 22.46 · high | 28.30 · good | poor |
| Fri 14:00 | 7.28 · high | 22.90 · high | 28.20 · good | poor |
| Fri 15:00 | 7.26 · high | 22.42 · high | 28.20 · good | poor |
| Fri 16:00 | 7.28 · high | 24.01 · high | 28.20 · good | poor |
| Fri 17:00 | 7.28 · high | 22.78 · high | 28.10 · good | poor |
| Fri 18:00 | 7.30 · high | 20.22 · high | 28.10 · good | poor |
| Fri 19:00 | 7.18 · high | 21.64 · high | 28.00 · good | poor |
| Fri 20:00 | 7.06 · high | 20.96 · high | 28.00 · good | poor |
| Fri 21:00 | 6.94 · high | 22.41 · high | 27.90 · good | poor |
| Fri 22:00 | 6.78 · high | 21.58 · high | 27.90 · good | poor |
| Fri 23:00 | 6.60 · high | 21.17 · high | 27.90 · good | poor |
| Sat 00:00 | 6.44 · high | 20.55 · high | 27.80 · good | poor |
| Sat 01:00 | 6.24 · high | 18.52 · high | 27.80 · good | poor |
| Sat 02:00 | 6.06 · high | 18.96 · high | 27.80 · good | poor |
| Sat 03:00 | 5.86 · high | 20.16 · high | 27.80 · good | poor |
| Sat 04:00 | 5.66 · high | 18.82 · high | 27.80 · good | poor |
| Sat 05:00 | 5.48 · high | 17.57 · high | 27.80 · good | poor |
| Sat 06:00 | 5.28 · high | 18.22 · high | 27.80 · good | poor |
| Sat 07:00 | 5.10 · high | 17.34 · high | 27.80 · good | poor |
| Sat 08:00 | 4.90 · high | 17.05 · high | 27.80 · good | poor |
| Sat 09:00 | 4.72 · high | 16.07 · high | 27.80 · good | poor |
| Sat 10:00 | 4.60 · high | 15.41 · high | 27.70 · good | poor |
| Sat 11:00 | 4.48 · high | 15.28 · high | 27.70 · good | poor |
| Sat 12:00 | 4.36 · high | 14.44 · high | 27.70 · good | poor |
| Sat 13:00 | 4.28 · high | 13.65 · high | 27.70 · good | poor |
| Sat 14:00 | 4.20 · high | 13.62 · high | 27.70 · good | poor |
| Sat 15:00 | 4.12 · high | 13.40 · high | 27.70 · good | poor |
| Sat 16:00 | 4.06 · high | 12.66 · high | 27.70 · good | poor |
| Sat 17:00 | 3.98 · high | 12.62 · high | 27.60 · good | poor |
| Sat 18:00 | 3.92 · high | 12.22 · high | 27.60 · good | poor |
| Sat 19:00 | 3.82 · high | 12.01 · high | 27.60 · good | poor |
| Sat 20:00 | 3.72 · high | 12.02 · high | 27.60 · good | poor |
| Sat 21:00 | 3.62 · high | 11.72 · high | 27.60 · good | poor |
| Sat 22:00 | 3.52 · high | 11.20 · high | 27.50 · good | poor |
| Sat 23:00 | 3.44 · high | 10.60 · high | 27.50 · good | poor |
| Sun 00:00 | 3.34 · high | 10.83 · high | 27.50 · good | poor |
| Sun 01:00 | 3.22 · high | 9.83 · high | 27.50 · good | poor |
| Sun 02:00 | 3.12 · high | 9.36 · high | 27.60 · good | poor |