September Weather in Fagatogo, American Samoa

Last updated: August 21, 2025

September in Fagatogo, American Samoa, showcases a tropical climate with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F). The average temperature stabilizes at a comfortable 27°C (80°F), making it a pleasant month for visitors. However, this period also brings considerable humidity levels at 84% and frequent rainfall, with 21 days of precipitation totaling 136 mm (5.4 in). This combination of warmth and moisture creates a lush, vibrant environment, perfect for experiencing the rich natural beauty and cultural rhythms of the region.

September Temperature in Fagatogo

In Fagatogo, American Samoa, September marks the transition into a slightly cooler yet still warm time of year. With minimum temperatures hovering around 25°C (77°F) and an average of 27°C (80°F), the month retains a tropical allure. The maximum temperature gently tapers off to 28°C (83°F), a reflection of the gradual shift towards the cooler months. Although September’s temperatures are comparable to those of the preceding summer months, they hint at the impending change of season, offering a comfortable climate for outdoor activities and exploration amidst the stunning natural beauty of the islands.

September Weather in Fagatogo: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Fagatogo, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Fagatogo, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec818181818181808080808081
Data source: Temperature data for Fagatogo generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Fagatogo

In September, Fagatogo experiences a moderate rainfall of 136 mm (5.4 in) spread over 21 days, marking a slight increase compared to the drier months of July (152 mm) and August (128 mm). This uptick hints at the transition into the wetter season, as precipitation levels begin to rise again leading into October. Notably, the overall trend indicates September is a pivotal month in the climatic rhythm of American Samoa, where rainfall acts as a precursor to the significantly wetter months ahead, notably November (266 mm) and December (360 mm), showcasing the region's vibrant tropical environment.

September Precipitation Trends in Fagatogo

The chart displays monthly precipitation patterns in Fagatogo, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Fagatogo, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec301464195228210178152129136225266360
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Fagatogo

In Fagatogo, American Samoa, September marks the peak of humidity, reaching 84%, which is part of an upward trend observed in the months leading up to it. Starting from 79% in the early months of the year, humidity gradually climbs, hitting 83% in August before making a significant leap in September. This increasingly humid environment signals the transition into the wetter season, as October follows with an even higher 85% humidity level. Overall, the data highlights a consistent pattern of rising humidity throughout the year, creating a notably moist tropical atmosphere that defines Fagatogo's climate.

September Average Humidity in Fagatogo

This chart illustrates the average monthly humidity levels in Fagatogo, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Fagatogo is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec79%80%79%79%80%80%81%83%84%85%82%82%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Fagatogo

In September, Fagatogo continues to experience an extreme UV Index of 14, reflecting the region's consistent exposure to intense sunlight as the dry season begins to wane. This trend follows a series of months with high UV levels, peaking at 16 in both January and February, and gradually tapering to 11 in May, before climbing again in August. With a steady burn time of just 10 minutes throughout these extreme months, it’s crucial for residents and visitors alike to stay vigilant about sun protection. As daylight hours shorten heading into October, the UV Index remains a stark reminder of the tropical sun's strength—underscoring the importance of sun safety. For more details, check the Fagatogo UV Index.

Maximum UV Index Levels in Fagatogo for September

The chart shows the monthly maximum UV Index (UVI) for Fagatogo in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Fagatogo typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec1616151311991214151515
Data source: Fagatogo September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Fagatogo

As the sun begins to set on summer and transitions into autumn, **September in Fagatogo, American Samoa, shines brightly with an impressive 301 hours of sunshine. This marks a delightful spike from the previous month, maintaining a steady upward trajectory that began in April. Following the trend of an increasingly sunny year, September's hours not only outshine July and August but also set the stage for an equally radiant October with even 308 hours anticipated. This pattern indicates a seasonally vibrant climate, perfect for outdoor adventures and soaking in the natural beauty of this tropical paradise. With sunshine steadily increasing from the year's quieter early months, September emerges as a wonderful time to embrace the warmth and light before the year's end.

Monthly Sunshine Duration in Fagatogo: September Highlighted

The September sunshine duration represents the total number of hours Fagatogo experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec232h224h310h272h281h264h271h293h301h308h299h290h
Data source: Fagatogo September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Fagatogo During September

As September rolls into Fagatogo, American Samoa, residents and visitors alike can rejoice in the notable increase in sunny weather, with a promising 75% chance of sunshine. This marks a significant rise compared to the earlier months of the year, particularly from the modest levels of January through April, where sunny days lingered below 50%. Following the mid-year peak in July, when the chances reached 64%, September emerges as a standout month, signaling a shift towards brighter and more enjoyable weather. Such trends highlight September as an ideal time for outdoor activities amidst the stunning surroundings of the islands.

Percentage of Sunny Days in September in Fagatogo

The chart illustrates the percentage of sunny days in Fagatogo throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Fagatogo experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec31%23%26%42%58%47%64%50%75%47%43%34%
Data source: Fagatogo September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Fagatogo in September

In September, Fagatogo, American Samoa, enjoys a return to 12 hours of daylight, a trend reminiscent of the earlier months of the year. This marks a shift from the slightly shorter days experienced during the mid-year months of April through August, which consistently offered 11 hours of sunlight. The equal daylight duration in January, February, March, and again in October through December creates a sense of continuity, while the month of September heralds the end of winter’s shorter days, bringing back that vibrant balance of light that characterizes much of the Samoan year. As daylight lengthens again, residents and visitors alike can relish the extended hours of sunshine, perfect for outdoor activities and beachside relaxation.

Average Daylight Hours in Fagatogo for September

The chart illustrates the variation in daylight duration in Fagatogo throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec12h 50m12h 32m12h 8m11h 44m11h 25m11h 16m11h 21m11h 38m12h 1m12h 25m12h 46m12h 56m
Data source: Fagatogo daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Fagatogo

In September, the winds in Fagatogo, American Samoa dance at an average speed of 6.0 m/s (13 mph), a gentle yet invigorating breeze that continues the trend of increasing wind speeds observed through the months of summer. Notably, July and August showcased the peak winds of the year at 7.3 m/s (16 mph) and 6.4 m/s (14 mph), respectively. As the island transitions into the heart of fall, September maintains a robust wind profile, slightly dipping from the summer highs but still breezy enough to invigorate the lush landscapes. Following this, October rebounds to 6.4 m/s (14 mph), hinting at an engaging seasonal rhythm where winds ebb and flow, creating an ever-refreshing atmosphere for both residents and visitors.

Average September Wind Speed in Fagatogo

The chart displays monthly wind speed patterns in Fagatogo, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec5.34.84.43.95.05.67.36.46.0 m/s6.44.95.0
Data source: Fagatogo September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Fagatogo Compares to Other Months

Weather in Fagatogo varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Fagatogo, focusing on differences in temperature, rainfall, humidity, and UV levels.

In September, the weather remains warm with temperatures averaging around 27°C (80°F) and a maximum of 28°C (83°F). However, this month experiences significant rainfall, with a total of 136 mm (5.4 in) spread over 21 days, leading to high humidity levels of 84%. In contrast, January sees slightly higher temperatures, with averages also around 27°C (82°F) but peaking at 29°C (85°F). Despite this, January is notably wetter, receiving 301 mm (11.8 in) of precipitation across 23 days, although the humidity is somewhat lower at 79%. For more detailed information about January weather in Fagatogo, you can visit Fagatogo weather in January.

In comparing the weather of September and February, we find that both months have similar average temperatures, with September averaging around 27°C (80°F) and February also at 27°C (81°F). However, February sees a slight increase in maximum temperature, reaching 30°C (86°F), compared to September’s 28°C (83°F). Rainfall is considerably more intense in February, with a staggering 464 mm (18.3 in) over 25 days, compared to September's 136 mm (5.4 in) over 21 days. Despite the higher precipitation in February, humidity levels are slightly lower at 80%, compared to September's 84%. For more detailed information, check out Fagatogo weather in February.

When comparing the weather in September and March, both months exhibit similar average temperatures, with September ranging from a minimum of 25°C (77°F) to a maximum of 28°C (83°F) and March slightly warmer at a minimum of 25°C (77°F) and a maximum of 29°C (85°F). However, March experiences more precipitation, totaling 195 mm (7.7 in) over 25 days, compared to September’s 136 mm (5.4 in) over 21 days. Additionally, the humidity levels in September are higher at 84%, while March sees a more moderate 79%. For more details on March weather, you can refer to Fagatogo weather in March.

When comparing the weather in September and April, both months showcase warm temperatures, with average highs hovering around 27-29°C (81-85°F). September tends to be slightly cooler, with an average max of 28°C (83°F), while April warms up just a bit more with a max of 29°C (85°F). In terms of precipitation, April is notably wetter, receiving 228 mm (9.0 in) over 25 days compared to September's 136 mm (5.4 in) over 21 days. Additionally, September has higher humidity levels at 84%, while April is slightly drier at 79%. For a closer look at April weather specifics, you can check Fagatogo weather in April.

In comparing the weather of September and May, both months observe similar average temperatures, hovering around 27°C (81°F), but May tends to be slightly warmer at times, with a maximum of 29°C (85°F). September experiences lower precipitation levels with 136 mm (5.4 in) over 21 days, while May sees increased rainfall at 210 mm (8.3 in) across 25 days. Additionally, September has a higher humidity level at 84%, compared to May’s 80%. For more detailed insights on May weather, you can visit Fagatogo weather in May.

In comparing the weather of September and June, both months exhibit similar average temperatures, with September reaching a minimum of 25°C (77°F) and an average of 27°C (80°F), while June has a slightly lower minimum of 24°C (76°F) but a higher maximum of 29°C (85°F). Precipitation levels are notably higher in June, with 178 mm (7.0 in) falling over 23 days compared to September's 136 mm (5.4 in) over 21 days. Humidity levels in September are a bit higher at 84%, compared to June's 80%. For more detailed insights, you can check the Fagatogo weather in June.

In comparing the weather between July and September, we see some notable similarities and differences. Both months have similar average temperatures, with a minimum of around 24°C to 25°C (76°F to 77°F) and maximums reaching 28°C (83°F). However, July experiences slightly less humidity at 81% compared to September's higher humidity level of 84%. Precipitation is also heavier in July, totaling 152 mm (6.0 in) over 24 days, while September has 136 mm (5.4 in) across 21 days. For more detailed information about July weather, you can check out Fagatogo weather in July.

In comparing the weather between August and September, both months experience similar temperature ranges with September showing a slight increase in the minimum temperature at 25°C (77°F) compared to August's 24°C (76°F). The average temperatures remain consistent at approximately 27°C (80°F), with maximums also peaking at 28°C (83°F) for both months. However, September brings more precipitation, totaling 136 mm (5.4 in) over 21 days, compared to August's 128 mm (5.1 in) over 20 days. The humidity is marginally higher in September at 84%, compared to 83% in August, contributing to a slightly more humid feel during the transition into fall. For more detailed insights into August weather in Fagatogo, you can check the following link: Fagatogo weather in August.

September and October exhibit similar temperatures, with average highs around 27°C (80°F) and lows consistently near 25°C (77°F). However, October tends to be slightly warmer with a maximum reaching 29°C (84°F). In terms of precipitation, October sees a significant increase, with 225 mm (8.9 in) of rain over 23 days compared to September's 136 mm (5.4 in) across 21 days. This shift brings a marginal increase in humidity as well, rising from 84% in September to 85% in October. For a more detailed view of the weather patterns during this month, you can check Fagatogo weather in October.

September and November exhibit similar warm temperatures, with September averaging around 27°C (80°F) and November slightly warmer at 27°C (81°F). However, while September experiences a lower total precipitation of 136 mm (5.4 in) over 21 days, November sees a significant increase to 266 mm (10.5 in) across 24 days, indicating a wetter trend as the months transition into late fall. Additionally, humidity levels remain relatively close, with September at 84% and November slightly lower at 82%. This shift in weather patterns points to more frequent rainy days in November, making it a notably wetter month. For more details, check out Fagatogo weather in November.

In comparing the weather between September and December, both months show similar temperature patterns, with minimum temperatures averaging around 25°C (77°F) and maximums reaching up to 29°C (84°F) in December. However, December experiences significantly higher precipitation, with 360 mm (14.2 in) falling over 29 days, compared to September's 136 mm (5.4 in) spread over 21 days. Humidity levels remain relatively consistent, at 84% in September and slightly lower at 82% in December. For more detailed insights on December weather, you can check Fagatogo weather in December.

Compare Fagatogo's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Fagatogo

September in Fagatogo stands out with its high humidity and a significant amount of rainfall, making it one of the wetter months of the year. While temperatures remain consistently warm, the combination of frequent rain and elevated humidity levels creates a notably muggy atmosphere. This contrasts sharply with the drier months, where sunshine predominates and rainfall is less frequent. Visitors can expect a lively tropical ambiance, best suited for those who appreciate vibrant nature and lush surroundings. For further details on seasonal variations, explore our page on Fagatogo Climate.