Ascension Island weather in September 2025

Q: How hot is it in Ascension Island in September?

Daytime temperatures usually reach 26°C in Ascension Island in September with low heat and humidity, falling to 23°C at night.

Q: How sunny is it in Ascension Island in September?

There are normally 6 hours of bright sunshine each day in Ascension Island in September - that's 46% of daylight hours.

Q: How warm is the sea around Ascension Island in September?

The average sea temperature around Ascension Island in September is 24°C.

Q: Does it ever rain in Ascension Island in September?

There are usually 17 days with some rain in Ascension Island in September and the average monthly rainfall is 36mm.

Expect 26°C daytime maximum temperatures in the shade with on average 6 hours of sunshine per day in Ascension Island in September. Check more long-term weather averages for Ascension Island in September before you book your next holiday to St Helena & Islands in 2025/2026.

26
26°C max day temperature
6
6 hours of sunshine per day
17
17 days with some rainfall
23
23°C min night temperature
12
12 hours of daylight per day
L
Low heat & humidity
36
36 mm of monthly rainfall
11
11+ (Extreme) UV index
24
24°C sea temperature

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The September weather guide for St Helena & Islands (Ascension Island) shows long term weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

Metric (°C / mm) | Imperial (°F / inches)

How hot is it in Ascension Island in September?

Daytime temperatures usually reach 26°C in Ascension Island in September with low heat and humidity, falling to 23°C at night.

How sunny is it in Ascension Island in September?

There are normally 6 hours of bright sunshine each day in Ascension Island in September - that's 46% of daylight hours.

How warm is the sea around Ascension Island in September?

The average sea temperature around Ascension Island in September is 24°C.

Does it ever rain in Ascension Island in September?

There are usually 17 days with some rain in Ascension Island in September and the average monthly rainfall is 36mm.

Ascension Island September sunrise & sunset times

Browse the sunrise and sunset times for Ascension Island in September 2025. Select a month to view Ascension Island sunrise and sunset times for the next 12 months.

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