Best Time to Dive Guanacaste
Across 4 Guanacaste dive sites with multi-year conditions history, March historically shows the most favorable days — 92% of sampled days in the good band. The next-highest months are August (90%), April (86%) and May (84%). January historically shows the fewest favorable days (76% of sampled days). Average water temperature in the sample runs from about 27°C in February to 30°C in May. Typical seas range from 1.0 m to 1.2 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 Guanacaste?
| Month | Historically favorable days | Water temp | Typical seas |
|---|---|---|---|
| Jan | 76% | 27°C | 1.1 m |
| Feb | 78% | 27°C | 1.0 m |
| Mar | 92% | 29°C | 1.0 m |
| Apr | 86% | 29°C | 1.0 m |
| May | 84% | 30°C | 1.1 m |
| Jun | 82% | 30°C | 1.2 m |
| Jul | 83% | 29°C | 1.1 m |
| Aug | 90% | 30°C | 1.1 m |
| Sep | 82% | 30°C | 1.2 m |
| Oct | 84% | 29°C | 1.2 m |
| Nov | 80% | 28°C | 1.2 m |
| Dec | 77% | 28°C | 1.0 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 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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