Best Time to Dive Alaska
Across 4 Alaska dive sites with multi-year conditions history, July historically shows the most favorable days — 100% of sampled days in the good band. The next-highest months are August (99%), June (98%) and February (98%). November historically shows the fewest favorable days (88% of sampled days). Average water temperature in the sample runs from about 4°C in March to 15°C in August. Typical seas range from 0.4 m to 0.9 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 Alaska?
| Month | Historically favorable days | Water temp | Typical seas |
|---|---|---|---|
| Jan | 96% | 4°C | 0.7 m |
| Feb | 98% | 4°C | 0.6 m |
| Mar | 95% | 4°C | 0.7 m |
| Apr | 94% | 5°C | 0.6 m |
| May | 97% | 7°C | 0.6 m |
| Jun | 98% | 11°C | 0.5 m |
| Jul | 100% | 14°C | 0.4 m |
| Aug | 99% | 15°C | 0.5 m |
| Sep | 93% | 12°C | 0.6 m |
| Oct | 90% | 9°C | 0.8 m |
| Nov | 88% | 6°C | 0.8 m |
| Dec | 90% | 5°C | 0.9 m |
% = share of sampled days scoring in the favorable band, median across 4 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.
Marine life seasons
Sighting patterns across the wider Alaska & Aleutians region — not site-specific promises.
- OrcaMay–Aug
- Humpback whaleMar–Sep
Bars are Jan–Dec — months when sightings historically concentrate (GBIF occurrence records). Wildlife is never guaranteed.
Diving Alaska soon? Browse its dive sites with auto-updating 7-day condition windows — free, no account needed.
Choosing between destinations? Compare them month by month with the Trip PlannerPro