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Guam climate guide: monthly weather averages
The Guam climate guides are perfect for planning your holiday. Monthly weather averages give the best indication of what the weather is usually like for every month of the year including figures for temperature, rainfall and sunshine. The climate guide shown below is for Agana.
Temperature in Guam (°C)
|Max temperature (daytime)|
|Min temperature (night-time)|
Sunshine & Daylight in Guam
|Daily hours of sunshine|
|Daily hours of daylight|
Rainfall in Guam
|Number of days with some rain|
|Average monthly rainfall (mm)|
More climate for Guam
|UV Index (Maximum)|
|Heat & Humidity|
Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme
Metric (°C / mm) | Imperial (°F / inches)
More about Guam
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Guam climate overview
Guam is the most southerly island of the Marianas Archipelago, in the Pacific Ocean over 2,000 kilometres (1,250 miles) to the east of the Philippines. Colonial Spanish influences are still evident in the lively capital Agana, although Spain ceded Guam to the United States in 1898, and the American government now maintains two large bases on the island.
Tourism is Guam's leading industry, with visitors arriving mainly from Japan in search of duty free shopping. Though the island has some nice beaches the best is off-limits to non-military personnel.
The northern two-thirds of Guam consists of a raised rolling limestone plateau with pockets of dense jungle that give the island a truly tropical feel. The northern coast is rugged with cliffs dropping precipitously into the sea, where huge Pacific swells have hollowed out an intricate tunnel of sea-caves along the base.
The south of the island is basically volcanic with an elongated mountain ridge dividing the inland valleys and coastline. The far south widens into a landscape of high hills and valleys cut by streams and waterfalls. The rolling hills, which are steep in places are mostly grass-covered, with trees growing only in the protected more fertile valleys. The best beaches are found along the sheltered coastline of the west, home to blindingly white sand and coral reefs.
The climate is tropical with rainfall in all months becoming heavy during the peak rainy season from July to December. Rainfall eases during the drier season from January to June when March is usually the sunniest month. Temperatures are consistently warm or hot all year with high heat and humidity.
Guam climate by month
Check Guam climate for a particular month by selecting from the list below. Monthly climate guides include figures for temperature, rainfall, sunshine hours and sea temperature plus daily sunrise & sunset times.
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