Measurements:
°C
°F
Guam
84°F
SW 22 mph
Feels like: 90°F
Precip: 100%
World Resorts Northern Mariana Islands Guam Weather

Guam Sea Water Temperature

Current Sea Water Temperature:
+86.2°F
Maximum Sea Water Temperature in January: 88.2°F
Minimum Sea Water Temperature in January: 83.4°F
Average water temperature in January: 86.4°F

Sea Water Temperature for the Last 10 Days:

January 09 86.2°F January 04 87.2°F
January 08 86.2°F January 03 87.0°F
January 07 86.8°F January 02 87.0°F
January 06 86.8°F January 01 86.8°F
January 05 86.8°F December 31 86.8°F

When is the Warmest Sea for Guam?

According to our data for the last three years for Guam the highest average sea water temperature was in August, September and July.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for Guam was 88.8°F. The maximum and minimum values were 87.8°F and 89.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Guam was 88.9°F. The maximum and minimum values were 87.8°F and 89.8°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Guam was 88.5°F. The maximum and minimum values were 87.4°F and 89.4°F respectively.

Best Time to Visit Guam
The most sunny months:
July 5 days
August 5 days
September 5 days
The most warm months:
June 91.6 °F
July 91.5 °F
August 91.1 °F
Warmest sea temperature:
August 89.4 °F
September 89.4 °F
July 89.2 °F
The most cold months:
February 86.9 °F
January 87.6 °F
March 88.0 °F
The most rainy months:
October 15 days
August 14 days
September 14 days
The most windy months:
February 17 mph
December 17 mph
January 17 mph

Guam on the Weather Map

Northern Mariana Islands Resorts:
NAME
Guam +84
Rota +86
Saipan +84
Susupe +84
Tinian +84
24 Hours Weather Forecast
Guam
Local time: 23:10
10 jan, saturday
0000 84°F
SW
22 mph
0300 84°F
SW
22 mph
0600 84°F
SW
22 mph
0900 84°F
SW
22 mph
1200 86°F
SW
23 mph
1500 86°F
SW
22 mph
1800 84°F
SW
22 mph
2100 84°F
SW
22 mph