American Samoa Weather, Seasons & Climate + Weather by Month

American Samoa Average Monthly Weather Data

American Samoa enjoys warm, tropical temperatures year-round due to its location just south of the Equator. There's very little variation in both air and sea temperatures throughout the year.

The hottest months are typically from December to April, when daytime highs average around 30°C (86°F), while the coolest period is from June to September, with average highs still a pleasant 28–29°C (82–84°F). Nighttime lows remain fairly consistent, averaging around 24°C (75°F) year-round.

American Samoa Year-Round Temperature: What is the Average Temperature in American Samoa?

The average maximum temperature in American Samoa is 29°C (84°F), while the average minimum is around 24°C (75°F).

Scroll down for temperature listings for each month in American Samoa.

The Sea Temperature in American Samoa

Like its air temperature, the sea temperature in American Samoa stays reliably warm throughout the year. With its year-round tropical climate, the ocean is always inviting for swimming, snorkelling and water sports.

The average annual sea temperature hovers around 28.5°C (83.3°F), offering perfect conditions for enjoying the South Pacific.

The warmest water temperatures are typically felt during the wet season, with the average sitting at 29°C (84°F) from November to April.

Even during the dry season between May and October, the sea remains pleasant, with average temperatures only dipping slightly to around 28°C (82°F).

Scroll down to see monthly sea temperatures in American Samoa in our detailed weather guides.

Don't be too swayed by the labels "dry" and "wet" season, rainfall in American Samoa is possible throughout the year. The islands receive an average of around 2,897 mm (114 in) of rain annually, with rain falling on approximately 113 days of the year.

As expected, the wet season (November to April) brings the heaviest rainfall, averaging between 249 to 394 mm (9.8 to 15.5 in) per month. This is also when tropical downpours and storm activity are most frequent.

During the dry season (May to October), American Samoa still sees occasional rain, with monthly rainfall ranging from 124 to 233 mm (4.9 to 9.2 in). While this period is drier and more settled, short showers, often heavy, can still roll in especially in the evenings or early mornings.

Thanks to the island's lush, volcanic terrain, inland areas tend to get more rain than the coastal zones. Regional micro-climates also mean that if it's raining in one village, it might be sunny just a few kilometres away.

American Samoa enjoys long daylight hours throughout the year, with around 13 hours of daylight daily from November to February. During the dry season (May to October), daylight drops slightly to about 11 to 12 hours, with June having the shortest days.

Sunshine-wise, the sunniest months are typically from August to October, when the islands see an average of 5-6 hours of bright sunshine per day. Meanwhile, December and January are usually the cloudiest months, with only about 5 hours of sunshine on average.

American Samoa, located in the South Pacific cyclone belt, is at risk of tropical cyclones during the wet season from November to April. The highest risk months are December, January and February, with an increased chance of activity during El Niño years.

The territory has experienced several major cyclones. Cyclone Val (1991) severely impacted the islands, causing widespread destruction to homes, schools and infrastructure. Cyclone Heta (2004) brought storm surges and power outages, whilst Cyclone Gita (2018) left significant flooding and property damage in its wake.

Whilst severe cyclones are relatively rare, American Samoa has well-established emergency response plans in place. For peace of mind, check forecasts regularly and read our Cyclone Safety in American Samoa LINK#TT030 guide to stay prepared during cyclone season.

The year kicks off hot, humid and wet in American Samoa, right in the middle of the wet and cyclone season. Expect frequent showers and high humidity. It’s also the cyclone season in the South Pacific, so be aware of cyclone warnings – see our cyclone guide LINK#TT030 for more details. Otherwise, the country is vibrant with New Year celebrations, as one of the last places on Earth to welcome the New Year.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 394 mm (15.5 in)
Daylight hours: 13 hours

For more in-depth information, see our complete guide to American Samoa Weather in January.

February remains sizzling and humid, with regular, intense afternoon showers. It’s still cyclone season, so stay alert for storm updates. The lush green landscape and fewer tourists make it a peaceful, verdant time to explore hidden waterfalls and rainforest paths.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 308 mm (12 in)
Daylight hours: 13 hours

For more in-depth information, see our complete guide to American Samoa Weather in February.

March offers more of the same tropical warmth and humidity, although rainfall may slightly ease compared to earlier months. It’s still wet but transitioning. You’ll find fewer crowds, making it ideal for snorkelling and enjoying cultural events.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 319 mm (12.6 in)
Daylight hours: 12 hours

For more in-depth information, see the complete guide to American Samoa Weather in March.

April marks the tail end of the wet season. Showers become less frequent and sunshine increases, although humidity remains high. The island feels fresh and vibrant, perfect for early morning treks or secluded beach visits before the drier season arrives.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 249 mm (9.8 in)
Daylight hours: 12 hours

For more in-depth information, see our full guide to American Samoa Weather in April.

May ushers in the dry season. Rainfall begins dropping, the heat remains pleasant, and humidity starts to ease. Expect about four hours of sunshine daily. It's a comfortable time to enjoy outdoor activities like kayaking, cultural tours and exploring beaches.

Average temperature: 29°C (84.2°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 198 mm (7.8 in)
Daylight hours: 11 hours

For more in-depth information, see our complete guide to American Samoa Weather in May.

June ranks as one of the driest months of the year, making it absolutely perfect for outdoor adventures. You'll love the cooler evenings, comfortable humidity levels and reliably dry conditions, ideal for tackling Rainmaker Mountain on foot or hopping on a ferry to explore the nearby islets.

Beach days are nothing short of magical, and you can count on rain being a rare occurrence during this delightful month.

Average temperature: 29°C (84°F) in the day, 23°C (73.4°F) at night
Average sea temperature: 28°C (82°F)
Average rainfall: 159 mm (6.3 in)
Daylight hours: 11 hours

For more in-depth information, see the complete guide to American Samoa Weather in June.

In July, dry-season bliss continues. Expect daily sunshine and minimal showers. Balmy days and warm seas make it ideal for water-based fun, from snorkelling to paddleboarding. UV protection is still recommended during prolonged outdoor adventures.

Average temperature: 29°C (84°F) in the day, 23°C (73°F) at night
Average sea temperature: 28°C (82°F)
Average rainfall: 124 mm (4.9 in)
Daylight hours: 11 hours

For more in-depth information, see the complete guide to American Samoa Weather in July.

August remains dry, sunny and pleasantly warm with the lowest humidity of the year. Water visibility peaks, making it a superb month for diving and reef exploration. Visitors will find calm seas and cloudless skies, perfect for beachside relaxation.

Average temperature: 28°C (82.4°F) in the day, 23°C (73°F) at night
Average sea temperature: 27°C (80.6°F)
Average rainfall: 146 mm (5.7 in)
Daylight hours: 12 hours

For more in-depth information, see the complete guide to American Samoa Weather in August.

September maintains the dry-season calm: mild humidity, little rain and steady sunshine. It’s a quieter time before the shoulder season picks up. Travel deals and peaceful villages await those seeking a tranquil island experience.

Average temperature: 29°C (84°F) in the day, 23°C (73°F) at night
Average sea temperature: 28°C (82°F)
Average rainfall: 174 mm (6.9 in)
Daylight hours: 12 hours

For more in-depth information, see the complete guide to American Samoa Weather in September.

October signals a gentle return of the wet season. Brief, tropical showers may appear, often in the afternoon. Temperatures stay warm and humidity rises slightly. Still a great time to visit, with fewer tourists and vibrant island life to enjoy.

Average temperature: 29°C (84°F) in the day, 23°C (73.4°F) at night
Average sea temperature: 28°C (82°F)
Average rainfall: 233 mm (9.2 in)
Daylight hours: 12 hours

For more in-depth information, see the complete guide to American Samoa Weather in October.

November marks the start of the wet season. Rainfall increases and humidity intensifies. The lush jungle comes alive, but you may encounter sudden showers. It’s also a good time to be aware of cyclone alerts and monitor forecasts closely.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 28°C (82.4°F)
Average rainfall: 252 mm (9.9 in)
Daylight hours: 13 hours

For more in-depth information, see the complete guide to American Samoa Weather in November.

December is wet, humid and increasingly prone to tropical storms as the wetter months continue. Despite the rain, festive holiday activities carry on with Christmas celebrations, church events and a rich, cultural atmosphere—so the tropical “Christmas spirit” is very much alive. Also, be aware that the holiday season is a busy time to fly to American Samoa, so make your bookings well in advance.

Average temperature: 30°C (86°F) in the day, 24°C (75°F) at night
Average sea temperature: 29°C (84°F)
Average rainfall: 341 mm (13.4 in)
Daylight hours: 13 hours

For more in-depth information, see the complete guide to American Samoa Weather in December.

Now that you know about the weather patterns in American Samoa, here are the answers to the internet's frequently asked questions about American Samoa's climate and weather conditions!

What is the best time to visit American Samoa weather-wise?

The best time to visit American Samoa is during the dry season from May to October when you'll experience less rainfall and more comfortable humidity levels. Temperatures remain consistently warm year-round, averaging 28-30°C (82-86°F).

Does American Samoa have a hurricane season?

Yes, American Samoa's cyclone season runs from November to April, with the highest risk typically occurring between December and March. However, direct hits are relatively rare due to the islands' location. For more information, check out Cyclone Safety in American Samoa LINK#TT030.

Is American Samoa humid all year round?

Yes, American Samoa maintains high humidity levels throughout the year, typically ranging from 75-85%. The trade winds help provide some relief, particularly during the dry season months.

What should I pack for American Samoa's weather?

Pack lightweight, breathable clothing, a reliable rain jacket, sun protection, and quick-dry fabrics. Don't forget waterproof bags for your electronics during the rainy season. For more information, check out What to Pack for American Samoa: American Samoa Packing List.

Which month has the most rain in American Samoa?
In terms of rainfall, January is usually the wettest month in American Samoa with 394 mm (15.5 in) on average. There are normally 18 days in January with some rain.