Guam Scuba Diving Conditions
Visibility peaks at 31–35 m (excellent) in January (DiveSight Visibility Score). Best time to dive: In May to July and September, the sea is calmest. The water stays a warm 28–30°C all year..
Data updated July 2026
Typical conditions in July across Guam
Area-level averages across 61 dive sites. Individual site conditions vary. Live per-site forecasts are available in the app.
DiveSight Visibility Score by month
Area-level averages across 61 dive sites in Guam.
| Month | Visibility (DVS) | Water temp | Swell |
|---|---|---|---|
| Januarybest | 31–35 mexcellent | 28 °C | 1.8 m |
| February | 25–30 mexcellent | 28 °C | 1.8 m |
| March | 10–25 mgood | 28 °C | 1.6 m |
| April | 21–29 mexcellent | 29 °C | 1.4 m |
| May | 21–29 mexcellent | 29 °C | 1.1 m |
| June | 21–29 mexcellent | 30 °C | 1.0 m |
| July | 21–29 mexcellent | 30 °C | 1.1 m |
| August | 10–25 mgood | 30 °C | 1.3 m |
| September | 28–32 mexcellent | 30 °C | 1.2 m |
| October | 26–31 mexcellent | 30 °C | 1.3 m |
| November | 30–33 mexcellent | 30 °C | 1.5 m |
| December | 21–29 mexcellent | 29 °C | 1.8 m |
DiveSight Visibility Score: our calibrated visibility model over 10yr of satellite and ocean-reanalysis data across 61 dive sites in this area, validated against diver reports. Area-level averages; individual sites vary.
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