Best Time to Dive Long Island
Across 1 Long Island dive sites with multi-year conditions history, May historically shows the most favorable days — 100% of sampled days in the good band.
Computed from our own conditions climatology — measured history, not brochure copy. Historical patterns, never a forecast or a guarantee.
Month by month
| Month | Historically favorable days | Water temp | Typical seas |
|---|---|---|---|
| Jan | 87% | 26°C | 0.9 m |
| Feb | 87% | 26°C | 1.0 m |
| Mar | 86% | 26°C | 0.9 m |
| Apr | 83% | 27°C | 0.9 m |
| May | 100% | 28°C | 0.7 m |
| Jun | 98% | 29°C | 0.8 m |
| Jul | 96% | 30°C | 0.9 m |
| Aug | 94% | 30°C | 0.8 m |
| Sep | 96% | 30°C | 0.7 m |
| Oct | 83% | 30°C | 1.0 m |
| Nov | 80% | 28°C | 1.0 m |
| Dec | 78% | 27°C | 1.1 m |
% = share of sampled days scoring in the favorable band, median across 1 sites with at least two years of history. Ringed = historical peak.
How does this compare worldwide? The Most Reliable Diving Months on Earth ranks 61 countries by the same measure.
Marine life seasons
Sighting patterns across the wider Caribbean & Bahamas region — not site-specific promises.
- Giant oceanic manta rayOctober
- OrcaJanuary
- Green sea turtleMar–May
- Bull sharkFebruary
- Humpback whaleAug–Sep
Bars are Jan–Dec — months when sightings historically concentrate (GBIF occurrence records). Wildlife is never guaranteed.
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