St Lucia weather in September 2019

  • 30°C maximum daytime temperature in September in St Lucia (Castries)30
    30°C max day temperature
  • 8 hours of sunshine per day
  • 25 days with some rainfall in September in St Lucia (Castries)25
    25 days with some rainfall
  • 24°C minimum night-time temperature in September in St Lucia (Castries)24
    24°C min night temperature
  • 12 hours of daylight per day in September in St Lucia (Castries)12
    12 hours of daylight per day
  • Very high heat & humidity in September in St Lucia (Castries)VH
    Very High heat & humidity
  • 224 mm monthly rainfall in September in St Lucia (Castries)224
    224 mm of monthly rainfall
  • UV (maximum) index 11+ (Extreme) in September in St Lucia (Castries)11
    11+ (Extreme) UV index
  • 29°C sea temperature in September in St Lucia (Castries)29
    29°C sea temperature
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The September weather guide for St Lucia, represented by 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.

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

Guide to St Lucia weather in September

The average maximum daytime temperature in St Lucia in September is a hot 30°C (86°F) with very high heat & humidity. The average night-time temperature is usually a warm 24°C (75°F). There are usually 8 hours of bright sunshine each day, which represents 62% of the 12 hours of daylight.

Expect 224mm (8.8 inches) of rainfall across the whole of September with 25 days with some rain falling. Maximum UV levels will be extreme (11+ UV index) at midday when the skies are clear.

The average sea temperature in and around St Lucia in September is 29°C (84°F).

The weather in St Lucia in September is represented by Castries.

St Lucia sunrise & sunset times for September 2019

Browse the sunrise & sunset times for St Lucia in September 2019. Select a month to view St Lucia sunrise & sunset times for the next twelve months. The St Lucia sunrise & sunset times shown below are for Castries.

JanFebMarAprMayJunJulAugSepOctNovDec

Date Sunrise times Sunset times
Sunday, 1st September 2019 05:52 18:16
Sunday, 15th September 2019 05:53 18:05
Monday, 30th September 2019 05:53 17:54
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