September weather forecastApia, Samoa

September
Weather in September
September in Apia, Samoa sees a continuation of the tropical climate with subtle shifts marking the transition phase. The average rainfall hits a yearly low with only 57mm (2.24") spread across approximately 19 days. This creates a noticeably drier spell when compared to August and the approaching October. The onset of cooler winds creates refreshing early morning and late evening periods. Despite these changes, the city remains poised for beach activities as the ocean temperature remains attractive to swimmers.Temperature
Apia records the coldest temperatures in September, averaging a high of 27.3°C (81.1°F) and a low of 26.3°C (79.3°F).Heat index
September's mean heat index is computed to be a hot 30°C (86°F). With prolonged exposure and constant activity, one might feel exhausted and experience heat cramps.Evaluating the heat index requires understanding its values in the shade and with gentle winds. Under direct sunshine, the heat index values might be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', embodies the combination of air temperature and moisture content to illustrate perceived heat. The impression of weather on a person can be swayed by additional aspects, including metabolic variations, pregnancy, and activity levels. When you're directly under the sun's rays, remember that the heat index may surge by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to babies and toddlers. Kids frequently ignore the importance of taking a break and rehydrating. Thirst is a late symptom of dehydration - thus, it is crucial to stay hydrated, especially during long-lasting physical activities.
Humidity
The months with the highest humidity are June through September, with an average relative humidity of 78%.Rainfall
The month with the least rainfall is September, when the rain falls for 18.7 days and typically collects 57mm (2.24") of precipitation.Sea temperature
August and September, with an average sea temperature of 27.9°C (82.2°F), are months with the coldest seawater.Note: For activities in the water such as swimming or diving, temperatures from 25°C (77°F) to 29°C (84.2°F) are considered optimal for prolonged enjoyment without discomfort.
Daylight
The average length of the day in September is 12h and 2min.On the first day of the month, sunrise is at 06:30 and sunset at 18:22. On the last day of September, sunrise is at 06:09 and sunset at 18:23 +13.
Sunshine
In Apia, Samoa, the average sunshine in September is 7.8h.UV index
January through December, with an average maximum UV index of 7, are months with the highest UV index. The months with the lowest UV index are January through December, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high threat to health from unsafe exposure to UV radiation for the ordinary person.Note: The maximum daily UV index of 7 in September interprets into the following recommendations:
Sidestep overexposure. Individuals with fair complexions risk burning in fewer than 20 minutes. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects. Stay alert! Reflective properties of sand and water amplify the Sun's UV radiation.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Apia, Samoa
- Average high temperature in September: 27.3°C
The warmest months (with the highest average high temperature) are March and April (28.7°C).
The month with the lowest average high temperature is September (27.3°C).
- Average low temperature in September: 26.3°C
The month with the highest average low temperature is January (27.6°C).
The coldest month (with the lowest average low temperature) is August (26°C).
Average pressure in September
Apia, Samoa
- Average pressure in September: 1012.3mbar
The month with the highest atmospheric pressure is September (1012.3mbar).
The month with the lowest atmospheric pressure is January (1007.5mbar).
Average wind speed in September
Apia, Samoa
- Average wind speed in September: 23.2km/h
The windiest month (with the highest average wind speed) is July (24.7km/h).
The calmest month (with the lowest average wind speed) is March (14.8km/h).
Average humidity in September
Apia, Samoa
- Average humidity in September: 78%
The months with the highest relative humidity are June, July, August and September (78%).
The month with the lowest relative humidity is March (75%).
Average rainfall in September
Apia, Samoa
- Average rainfall in September: 57mm
The wettest month (with the highest rainfall) is January (175mm).
The driest month (with the least rainfall) is September (57mm).
Average rainfall days in September
Apia, Samoa
- Average rainfall days in September: 18.7 days
The month with the highest number of rainy days is April (22.7 days).
The month with the least rainy days is September (18.7 days).
Average sea temperature in September
Apia, Samoa
- Average sea temperature in September: 27.9°C
The best month for swimming (with the highest average sea temperature) is March (29.7°C).
The coldest months (with the lowest average sea temperature) are August and September (27.9°C).
Average daylight in September /
Average sunshine in September
Apia, Samoa
- Average daylight in September: 12h and 0min
The month with the longest days is December (Average daylight: 12h and 54min).
The month with the shortest days is June (Average daylight: 11h and 18min).
- Average sunshine in September: 7h and 48min
The month with the most sunshine is March (Average sunshine: 8h and 42min).
The month with the least sunshine is July (Average sunshine: 7h and 18min).
Average sunshine days in September
Apia, Samoa
- Average sunshine days in September: 3.6 days
The month with the most sunshine days is December (10.4 days).
The month with the least sunshine days is June (2.7 days).
Average UV index in September
Apia, Samoa
- Average UV index in September: 7
The months with the highest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 7).
Average cloud cover in September
Apia, Samoa
- Average cloud cover in September: 44
The month with the most cloud cover is July (Cloud cover 49).
The month with the least cloud cover is March (Cloud cover 38).
Average visibility in September
Apia, Samoa
- Average visibility in September: 10km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (10km).








