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Guam weather in August

Weather in Guam: August

Average day temperature: 86.8°F
Average night temperature: 82.8°F
Sea water temperature: 85.4°F
Number of sunny days: 4 days
Day length: 12.4 - 12.7 hours
Number of rainy days: 13 days
Precipitation totals: 8.8 in.

Air temperature in August, °F

Show year:
2026
2025
2024

The highest day temperature during August of 2026 was 86°F. At the same time the lowest night temperature was 75°F. Daily and nightly averages during August were 83.5°F and 81.6°F.

Sea water temperature in Guam in August, °F

Show year:
2026
2025
2024

The average sea water temperature in August of 2026 was 84.7°F. The highest and lowest sea temperatures during the month were 85.8°F and 84.0°F.

Sunny, partly cloudy and cloudy days

Mostly all days in August are cloudy but sunny and partly cloudy days are also possible.

Precipitation total in August, in.

Precipitation total value in Guam in August is 9.5 in. Other months of the year show relatively similar values.

Wind speed in August, mph

The average wind speed value in August is 9.6 mph It makes August one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in August is: 4.6.

Best time for vacation in Guam

Sunniest months:
July 5 days
September 5 days
May 4 days
Warmest months:
June 87.3 °F
July 87.1 °F
August 86.8 °F
Warmest sea temp:
September 85.4 °F
August 85.4 °F
July 85.3 °F
Coldest months:
February 83.1 °F
January 83.8 °F
March 84.0 °F
Rainiest months:
October 15 days
September 14 days
July 13 days
Windiest months:
February 17.3 mph
December 17.2 mph
January 16.5 mph

Guam on a weather map

Guam
+82°F
SE 4 mph
Feels like: +91°F
Precip.: 58%
Places in Northern Mariana Islands:
Name
°F
+82°F
+82°F
+84°F
+84°F
+84°F
24 Hours Forecast
Guam
Local time: 00:20
September 20, sunday
0300
82°F
S
2 mph
0600
82°F
NW
2 mph
0900
84°F
N
4 mph
1200
84°F
N
4 mph
1500
84°F
NE
6 mph
1800
82°F
NE
4 mph
2100
82°F
NE
4 mph
September 21, monday
0000
82°F
NE
4 mph
Units of measurement: °C / °F