Last updated: April 14, 2025
The climate of American Samoa is characterized by warm temperatures and high humidity throughout the year, making it a tropical paradise. In February, temperatures range from a minimum of 24°C (75°F) on Swains Island to a maximum of 30°C (86°F) in Manu'a. Precipitation varies significantly by month, with Eastern District experiencing its peak rainfall in February, totaling 466 mm (18.3 in), while Manu'a sees its driest month in September with just 97 mm (3.8 in). Humidity levels are consistently high, averaging a minimum of 76% in December on Swains Island and peaking at 85% in October in Eastern District. This combination of heat and moisture creates a lush, vibrant environment, characterized by unique ecosystems and rich biodiversity.
American Samoa is characterized by a tropical rainforest climate, classified under the Köppen-Geiger system as Af across its regions. This includes the Eastern District, Manu'a, Swains Island, and Western District. As a result, expect lush greenery and abundant rainfall throughout the year, creating a vibrant ecosystem that is both breathtaking and inviting for nature enthusiasts. The consistently warm temperatures contribute to the island’s rich biodiversity, making it a unique tropical paradise.
| Climate Zone | Description |
|---|---|
| Af | Tropical rainforest climate with no dry season and high temperatures year-round. |
The temperatures in American Samoa exhibit a delightful consistency throughout the year, with monthly averages oscillating between a comfortable 24°C (75°F) and a balmy 30°C (86°F). January kicks off the year with a minimum of 25°C (77°F) on Swains Island and peaks at 29°C (85°F) in Manu'a. As February rolls in, a slight dip in minimum temperatures (24°C/75°F in Swains Island) is accompanied by a rise in maxima to 30°C (86°F) in Manu'a. This warm trend continues, with the temperatures hovering around 25°C to 29°C from March through April, showcasing minimal fluctuations. May flaunts its summery vibe with maxima peaking at 30°C (86°F) once more, particularly on Swains Island, while the hotter months of June to August see stable temperatures capped at 29°C (84°F) to 29°C (85°F) across various locations. September through December maintains this pleasant warmth, with consistent minimums of 24°C (76°F) and maximums around 29°C (85°F). The mild difference across the months reveals a tropical paradise, where temperatures are perpetually inviting for both relaxation and adventure.
In American Samoa, precipitation patterns reveal a dynamic interplay between wet and dry periods throughout the year. The rainiest month tends to be February, where Eastern District experiences an impressive 466 mm (18.3 in) of rainfall, while September in Manu'a marks the driest with a minimum of 97 mm (3.8 in). The number of rainy days further illustrates this variability, with a minimum of 18 days in August for Manu'a contrasting with the maximum of 29 days in December in Eastern District. These trends highlight the region's tropical climate, characterized by significant rainfall fluctuations, particularly as the year progresses from the drier to the wetter months. Such patterns not only influence the local environment but also shape the lifestyles of those who call this beautiful territory home.
American Samoa experiences notable humidity variations throughout the year, with levels consistently high across its regions. December marks the lowest point of humidity, particularly observed in Swains Island at 76%, while October sees a peak of 85% in the Eastern District. This trend highlights the tropical climate's influence, where humidity reaches its zenith in the warmer months, contributing to a lush and vibrant environment year-round. The consistent moisture levels play a vital role in supporting the region's rich biodiversity and spectacular landscapes.
American Samoa experiences consistently high UV Index levels, particularly evident in the months of January and February. Both the Eastern District and Manu'a report an average daily maximum UVI of 16 during these months, highlighting a trend of intense solar radiation during the peak of summer in the region. This remarkable consistency underscores the importance of sun protection measures as residents and visitors face similar risks from UV exposure across these two significant areas. As the summer unfolds, maintaining awareness of these trends is crucial for safeguarding health and enjoying the outdoor beauty that American Samoa has to offer.
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Sunshine duration in American Samoa reveals intriguing variations across its islands and months. In February, Swains Island receives 209 hours of sunshine, while Manu'a enjoys a slightly brighter month with 229 hours. As the seasons change to March, the sun shines even more generously, with Swains Island basking in 305 hours and the Eastern District reaching a peak of 310 hours. This trend indicates that as summer approaches, these islands experience a significant increase in sunshine, enhancing their appeal for visitors seeking vibrant tropical experiences.
In American Samoa, the probability of enjoying sunny weather varies significantly throughout the year, particularly noticeable on Swains Island. While February offers only a modest 17% chance of clear skies, by September, this figure skyrockets to an impressive 81%. This trend highlights the distinct seasonal shift, making late summer the ideal time for sun-seekers to visit and bask in the region's warmth and beauty.
In American Samoa, daylight hours fluctuate gracefully throughout the year, with the Eastern District experiencing approximately 11 hours of sunlight in June, which gradually increases to around 12 hours in December. This subtle shift reflects a tropical rhythm, where longer days in the latter part of the year invite more opportunities for outdoor activities and cultural celebrations. As the seasons change, residents and visitors alike can revel in the consistent warmth and vibrant landscapes that daylight provides, making every moment spent in this paradise feel special.
The Eastern District of American Samoa boasts a tropical climate characterized by warm temperatures and significant humidity year-round. With an average temperature consistently around 27°C (81°F), the district experiences slight variations from 25°C (77°F) in January to a peak of 30°C (86°F) in February. Rainfall is prominent, particularly in February with 466 mm (18.3 in), while the dry season typically settles in during late summer months. Humidity levels rise steadily, peaking at 85% in October, contributing to the lush landscapes that define this beautiful region. Discover more about the area's unique climate here.
The climate in Manu'a, American Samoa is characterized by warm tropical temperatures year-round, with averages hovering around 27°C (81°F). From January to April, the area experiences distinct precipitation patterns, peaking in February with an impressive 463 mm (18.2 in) of rain, while drier months like August see only 112 mm (4.4 in). Humidity remains notably high, typically ranging between 79% and 84%, contributing to the lush greenery that defines the landscape. Visitors can expect warm temperatures and a fair chance of rainfall throughout the year, making it an ideal destination for those who appreciate a vibrant tropical climate. For more details, check out Manu'a climate.
Swains Island, nestled in American Samoa, enjoys a warm tropical climate throughout the year, with average temperatures hovering around 27°C (81°F). Visitors can expect mild temperature variations, ranging from 24°C (75°F) to 30°C (86°F), creating an inviting atmosphere. Rainfall is prominent, especially in February, which sees up to 446 mm (17.6 in) of precipitation, contributing to the island's lush greenery. Humidity levels also rise during the warmer months, peaking at 82% in August. For more detailed insights on the weather, check out Swains Island climate.
The climate in the Western District of American Samoa is characterized by consistently warm temperatures, with average highs around 27°C (81°F) throughout the year. Nighttime temperatures rarely dip below 24°C (76°F), creating a tropical feel that is perfect for beach lovers. This region experiences a significant amount of rainfall, particularly in February, which sees nearly 464 mm (18.3 in), while the drier months of August and September receive only about 128 mm (5.1 in). Humidity levels typically hover between 79% and 85%, contributing to the lush vegetation that makes this area so breathtaking. For a deeper dive into the region's weather patterns, explore more about the Western District climate.
The climate of American Samoa exhibits a warm tropical pattern characterized by minimal temperature variation throughout the year, with February temperatures ranging from a comfortable 24°C (75°F) on Swains Island to a balmy 30°C (86°F) in Manu'a. Rainfall is most pronounced in February, where the Eastern District experiences maximum precipitation of 466 mm (18.3 in), contributing to the lush landscapes that define the region. Conversely, September sees the least amount of rainfall in Manu'a at just 97 mm (3.8 in), highlighting a dry spell that precedes the wetter months. Humidity levels add to the tropical feel, peaking at an average of 85% in October within the Eastern District, while December records a minimum of 76% on Swains Island. Overall, these climatic trends not only create a vibrant environment but also influence the unique flora and fauna that thrive across American Samoa's islands, making it a fascinating destination for nature lovers and climate enthusiasts alike.