Best Time to Dive Guadalcanal (Iron Bottom Sound
Across 1 Guadalcanal (Iron Bottom Sound, off Honiara) dive sites with multi-year conditions history, March, April, May, July, October, November and December historically show 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 | — | — | — |
| Feb | — | — | — |
| Mar | 100% | 30°C | 0.5 m |
| Apr | 100% | 31°C | 0.5 m |
| May | 100% | 30°C | 0.8 m |
| Jun | 93% | 30°C | 0.9 m |
| Jul | 100% | 29°C | 0.9 m |
| Aug | 95% | 29°C | 1.1 m |
| Sep | 93% | 29°C | 1.1 m |
| Oct | 100% | 30°C | 0.8 m |
| Nov | 100% | 30°C | 0.6 m |
| Dec | 100% | 31°C | 0.5 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 Micronesia & western Pacific region — not site-specific promises.
- Whale sharkDec–Jan
- Scalloped hammerheadFeb–Mar
- Humpback whaleJul–Oct
- Reef manta rayJun–Sep
- Tiger sharkyear-round
- Bull sharkyear-round
- Green sea turtleyear-round
Bars are Jan–Dec — months when sightings historically concentrate (GBIF occurrence records). Wildlife is never guaranteed.
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