Guam weather in September 2025
Guam weather in September 2025
Day
31 °C
Night
25 °C
Sea
29 °C
Precipitation
295 mm
in month
Rainy days
16 days
in month
Daylight
12 hours
average
Sunshine
5 hours
average
Humidity
89 %
Day
31 °C
Night
25 °C
Sea
29 °C
Precipitation
295 mm
in month
Rainy days
16 days
in month
Daylight
12 hours
average
Sunshine
5 hours
average
Humidity
89 %
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Weather overview and FAQs
Weather overview
In Guam in September, the average air temperature ranges from 31 °C (88 °F) during the day to 25 °C (76 °F) at night. There are 16 days of rain on average, where the rainfall is 295 mm (11.60 in).
Are there good conditions to visit in Guam in September?
There are good conditions for visiting in Guam in September. The daily temperatures in this month reach pleasant 31 °C (88 °F). The seawater temperature reaches ideal 29 °C (85 °F). At night, temperatures hover around a pleasant 25 °C (76 °F). In Guam in September, there is a wet season, which means that it could rain more often there during your stay.
What is the sea temperature in Guam in September?
In Guam in September expect the sea to be warm at 29 °C (85 °F). This temperature is someone's dream come true, while for someone it may no longer be ideal for the purpose of refreshment.
What is the temperature in Guam during the day in September?
In September in Guam, the average daily temperatures will be 31 °C (88 °F). The great temperature for lying by the sea or pool and sunbathing, everywhere else you will probably be a bit hot. Don't forget to drink during the day, in these temperatures you should hydrate yourself a lot.
What is the average number of rainy days in Guam in September?
There are 16 days, which are rainy in September in Guam, that is, days with precipitation more than 2 mm (0.08 in). Converted to days of the week, this means that it will occur on an average of 3.8 days of the week, or in general - 54 % days.
How heavy is the precipitation in September in Guam?
In Guam in September, there is 295 mm (11.60 in) rainfall, which means on average 10 mm (0.39 in) rainfall per day.
What is the air temperature in September in Guam at night?
The average night temperature in Guam in September is 25 °C (76 °F). A very pleasant temperature for long evening walks, fun over a drink outside, or doing sports in the morning. If possible, look for a hotel with air conditioning.
How many sunny hours can I expect in September in Guam?
There is an average length of sunshine of 5 hours per day in September in Guam.
Is there a wet season in September in Guam?
Yes, in September in Guam there is a wet season with 16 days, when there is rain in a month.
Is it hot in September in Guam?
In Guam in September, you will enjoy nice warm weather, but it will also be pleasant and you probably won't feel hot.
What level of humidity is to expect in Guam in September?
In September in Guam, expect humidity around 89 %. This humidity is rather above average, but except for sensitive individuals, it should not be a problem.
How long is the day (from dawn till dusk) in Guam in September?
The length of daylight in Guam in September is 12 hours.
How windy is it in Guam in September?
In Guam in September, there will be an average wind scale of 3.