Climate of Guam — Month by Month
Country-wide average for Guam. Part of Micronesia, Oceania.
Located in Micronesia, Oceania, Guam has a tropical climate. Country-wide average temperatures range from 26.5°C / 79.7°F in January to 28°C / 82.4°F in May, with annual rainfall totalling around 2245 mm / 88.4 in — driest in March (75 mm / 3 in), wettest in August (350 mm / 13.8 in). These are national averages; regional variation can be substantial, especially in geographically diverse countries. For city-level detail see the cities section below, and for state or province breakdowns follow the subdivisions link if available.
| Month | Temperature | Rainfall | Matches |
|---|---|---|---|
| January | 26.5°C79.7°F | 125 mm4.9″ | Tropical |
| February | 26.5°C79.7°F | 100 mm3.9″ | Tropical |
| March | 27°C80.6°F | 75 mm3″ | — |
| April | 27.5°C81.5°F | 90 mm3.5″ | Tropical |
| May | 28°C82.4°F | 110 mm4.3″ | Tropical |
| June | 28°C82.4°F | 145 mm5.7″ | Tropical |
| July | 27.5°C81.5°F | 250 mm9.8″ | Tropical |
| August | 27.5°C81.5°F | 350 mm13.8″ | Tropical |
| September | 27.5°C81.5°F | 350 mm13.8″ | Tropical |
| October | 27.5°C81.5°F | 300 mm11.8″ | Tropical |
| November | 27.5°C81.5°F | 200 mm7.9″ | Tropical |
| December | 27°C80.6°F | 150 mm5.9″ | Tropical |
Frequently asked questions
What is the best time to visit Guam?
Guam does not have a clear sunny-and-dry window by our cutoffs. The warmest month is May at 28°C / 82.4°F, and the driest is March at 75 mm / 3 in — likely your best travel window.
What is the climate of Guam?
Guam has country-wide monthly average temperatures ranging from 26.5°C / 79.7°F in January to 28°C / 82.4°F in May. Annual rainfall averages about 2245 mm / 88.4 in, with the wettest month being August (350 mm / 13.8 in) and the driest March (75 mm / 3 in). Regional variation within Guam can be significant — see subdivision or city pages for detail.
What is the hottest month in Guam?
The hottest month in Guam is May, with a country-wide average temperature of 28°C / 82.4°F.
What is the coldest month in Guam?
The coldest month in Guam is January, with a country-wide average temperature of 26.5°C / 79.7°F.
When does it rain most in Guam?
The wettest month in Guam is August, averaging about 350 mm / 13.8 in of rain. The driest is March with about 75 mm / 3 in.