St Helena weather in September 2025

Q: How hot is it in St Helena in September?

Daytime temperatures usually reach 18°C in St Helena in September, falling to 15°C at night.

Q: How warm is the sea around St Helena in September?

The average sea temperature around St Helena in September is 20°C.

Q: Does it ever rain in St Helena in September?

There are usually 12 days with some rain in St Helena in September and the average monthly rainfall is 54mm.

Expect 18°C daytime maximum temperatures in the shade with on average -9999 hours of sunshine per day in St Helena in September. Check more long-term weather averages for St Helena in September before you book your next holiday to St Helena & Islands in 2025/2026.

18
18°C max day temperature
12
12 days with some rainfall
15
15°C min night temperature
12
12 hours of daylight per day
0
No heat & humidity
54
54 mm of monthly rainfall
11
11 (Extreme) UV index
20
20°C sea temperature

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The September weather guide for St Helena & Islands (St Helena) 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 St Helena in September?

Daytime temperatures usually reach 18°C in St Helena in September, falling to 15°C at night.

How warm is the sea around St Helena in September?

The average sea temperature around St Helena in September is 20°C.

Does it ever rain in St Helena in September?

There are usually 12 days with some rain in St Helena in September and the average monthly rainfall is 54mm.

St Helena September sunrise & sunset times

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

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