Best Time to Dive United States
Across 1,011 United States dive sites with multi-year conditions history, July historically shows the most favorable days — 97% of sampled days in the good band. The next-highest months are August (91%), June (88%) and September (88%). March and December historically show the fewest favorable days (65% of sampled days). Average water temperature in the sample runs from about 13°C in February to 26°C in July. Typical seas range from 0.8 m to 1.3 m of significant wave height through the year. These figures are historical climatology computed from measured conditions — patterns, not a forecast or a guarantee.
Computed from our own conditions climatology — measured history, not brochure copy.
Which months are historically most favorable in the United States?
| Month | Historically favorable days | Water temp | Typical seas |
|---|---|---|---|
| Jan | 67% | 13°C | 1.3 m |
| Feb | 67% | 13°C | 1.3 m |
| Mar | 65% | 14°C | 1.3 m |
| Apr | 72% | 16°C | 1.2 m |
| May | 87% | 20°C | 1.0 m |
| Jun | 88% | 23°C | 0.9 m |
| Jul | 97% | 26°C | 0.8 m |
| Aug | 91% | 26°C | 1.0 m |
| Sep | 88% | 25°C | 1.1 m |
| Oct | 72% | 22°C | 1.2 m |
| Nov | 70% | 19°C | 1.2 m |
| Dec | 65% | 15°C | 1.3 m |
% = share of sampled days scoring in the favorable band, median across 1011 dive 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.
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