The destination comparison · Historical conditions
Best Places to Snorkel in Hawaii
Compare historical Snorkel Scores, calm-water percentages, water temperatures and best months from stored forecast data.
3 monitored destinations · 1 Sep 2025–31 Aug 2026 · How we rank
| Destination | Score / 100 | Calm-water % | Mean water temp | Best months |
|---|---|---|---|---|
| 1. MauiUSA · 8760 sampled hoursOffshore model point: 20.79°, -156.46°Water-temperature climate · Live report | 25.9 | 0.0% | 26.3°C79.4°F | Jun, Jul, May |
| 2. KauaiUSA · 8760 sampled hoursOffshore model point: 21.96°, -159.71°Water-temperature climate · Live report | 23.3 | 0.0% | 26.3°C79.3°F | Jun, May, Apr |
| 3. OahuUSA · 8760 sampled hoursOffshore model point: 21.29°, -158.04°Water-temperature climate · Live report | 21.3 | 0.0% | 26.0°C78.9°F | Jun, May, Jul |
Methodology and coverage
These are historical MeteoFrance wave and ocean model fields combined with ERA5 wind, cloud and daylight data through Open-Meteo. We calculate and store monthly Snorkel Scores from these inputs. They are model estimates, not in-water observations or a long-term climate normal. The comparison uses 1 Sep 2025–31 Aug 2026 in UTC. Future forecast hours are excluded.
- Coverage: curated destinations and Hawaii island hubs, excluding their nested beach rows and freshwater Crystal River. Each destination must have at least 20 qualifying days in each of all 12 months. A day needs at least 18 valid hourly samples. Wave height, wind, water temperature, cloud cover, daylight, sea level and current data must be present. All rows use the same scoring version and fixed models. We sample wind at the resolved offshore wave point instead of an inland island centre. Missing inputs are excluded.
- Snorkel Score: the hourly score on a 0–1 scale, multiplied by 100. It reflects waves, wind, temperature, daylight and available tide/current and cloud inputs. We average hours within each day, days within each month, then give all 12 months equal weight. Nighttime hours remain included and receive zero in the scoring system. This is an all-hours comparison, not the average score of daylight snorkeling sessions. The historical calculation uses the live scoring formula with a fixed 72-hour centred tidal range and the provider's daylight flag. Captured forecast scores are not mixed into these rows.
- Calm-water percentage: the share of valid sampled hours with waves at or below 0.36 m and wind at or below 5.4 m/s, averaged by day and month in the same way. It is an archive frequency, not a prediction of safe swimming. Currents, visibility, tides and local hazards are not part of this calm-water definition.
- Water temperature: the mean historical sea-surface temperature, weighted equally by day and month. Follow the climate link for the destination's separate monthly temperature baseline and source years.
- Best months: the three highest-scoring months in this window, listed in score order. Ties use calendar order. Destination ties use name, then URL. A single year's pattern may not repeat.
Coverage limits the shortlist: unmonitored destinations are absent. Forecast grid points cannot resolve every sheltered cove. This ranking does not measure coral health, wildlife, water clarity, access or operator quality. Check the live report and local guidance before entering the water.
Sources: Open-Meteo Marine API and ERA5 via the Historical Weather API. Commercial placements do not affect scores or order.
Which Hawaiian island is best for snorkeling?
Use the destination rows to compare the monitored coasts of each island. A forecast point does not represent every shore of an island. After choosing an island, use our Maui and Oahu spot guides to choose a beach.