St Barthelemy weather in September 2025

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

Daytime temperatures usually reach 31°C in St Barthelemy in September with very high heat and humidity, falling to 25°C at night.

Q: How sunny is it in St Barthelemy in September?

There are normally 8 hours of bright sunshine each day in St Barthelemy in September - that's 63% of daylight hours.

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

The average sea temperature around St Barthelemy in September is 29°C.

Q: Does it rain in St Barthelemy in September?

There are usually 19 days with some rain in St Barthelemy in September and the average monthly rainfall is 129mm.

Q: What is the chance of a hurricane in St Barthelemy in September?

On average 1.2 days in September in St Barthelemy are likely to be affected by the passage of one or more tropical storms.

Expect 31°C daytime maximum temperatures in the shade with on average 8 hours of sunshine per day in St Barthelemy in September. Check more long-term weather averages for St Barthelemy in September before you book your next holiday to St Barthelemy in 2025/2026.

31
31°C max day temperature
8
8 hours of sunshine per day
19
19 days with some rainfall
25
25°C min night temperature
12
12 hours of daylight per day
VH
Very High heat & humidity
129
129 mm of monthly rainfall
11
11+ (Extreme) UV index
29
29°C sea temperature

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The September weather guide for St Barthelemy 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 Barthelemy in September?

Daytime temperatures usually reach 31°C in St Barthelemy in September with very high heat and humidity, falling to 25°C at night.

How sunny is it in St Barthelemy in September?

There are normally 8 hours of bright sunshine each day in St Barthelemy in September - that's 63% of daylight hours.

How warm is the sea around St Barthelemy in September?

The average sea temperature around St Barthelemy in September is 29°C.

Does it rain in St Barthelemy in September?

There are usually 19 days with some rain in St Barthelemy in September and the average monthly rainfall is 129mm.

What is the chance of a hurricane in St Barthelemy in September?

On average 1.2 days in September in St Barthelemy are likely to be affected by the passage of one or more tropical storms.

St Barthelemy September sunrise & sunset times

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

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