Castries weather in September 2025

Expect 30°C daytime maximum temperatures in the shade with on average 8 hours of sunshine per day in Castries in September. Check more long-term weather averages for Castries in September before you book your next holiday to St Lucia in 2025/2026.

  • 30°C maximum daytime temperature in September in Castries30
    30°C max day temperature
  • 8 hours of sunshine per day
  • 25 days with some rainfall in September in Castries25
    25 days with some rainfall
  • 24°C minimum night-time temperature in September in Castries24
    24°C min night temperature
  • 12 hours of daylight per day in September in Castries12
    12 hours of daylight per day
  • Very high heat & humidity in September in CastriesVH
    Very High heat & humidity
  • 224 mm monthly rainfall in September in Castries224
    224 mm of monthly rainfall
  • UV (maximum) index 11+ (Extreme) in September in Castries11
    11+ (Extreme) UV index
  • 29°C sea temperature in September in Castries29
    29°C sea temperature

More about Castries

Castries by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for St Lucia

TUI: up to 7% off holidays booked online

  • Book online with TUI & save up to 7% on holidays
  • FREE child places available for select holidays
  • Pay £0 deposits with direct debit & spread the cost
Go to TUI deal >>

View all TUI offers

TUITUI deal finder

The September weather guide for St Lucia (Castries) 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)

Back to top

More about St Lucia

How hot is it in Castries in September?

Daytime temperatures usually reach 30°C in Castries in September with very high heat and humidity, falling to 24°C at night.

How sunny is it in Castries in September?

There are normally 8 hours of bright sunshine each day in Castries in September - that's 62% of daylight hours.

How warm is the sea around Castries in September?

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

Does it rain in Castries in September?

There are usually 25 days with some rain in Castries in September and the average monthly rainfall is 224mm.

What is the chance of a hurricane in Castries in September?

On average 1.1 days in September in Castries are likely to be affected by the passage of one or more tropical storms.

Castries September sunrise & sunset times

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

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Monday, 1st September 2025 05:52 18:15
Monday, 15th September 2025 05:53 18:05
Tuesday, 30th September 2025 05:54 17:54

Related posts

Popular travel offers

Explore holidays in the sun for less

More holidays

Airport parking

More parking

Airport lounges

More lounges

Top ^