St Lucia weather by month
St Lucia is warmest in September (30°C average high) and coolest in January (27°C). For warm, mostly dry weather, go February to April. The sea is warm enough for easy swimming all year.
Warmest month
September
30°C
Coolest month
January
27°C
Wettest month
July
129 mm
Flight from London
8½h
direct, estimated
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St Lucia temperature by month
Tap a month for the detail and warmer alternatives.
| Month | Day | Night | Sea | Rain |
|---|---|---|---|---|
| January | 27°C | 24°C | 28°C | 70 mm |
| February | 27°C | 24°C | 27°C | 54 mm |
| March | 28°C | 24°C | 27°C | 55 mm |
| April | 29°C | 25°C | 28°C | 45 mm |
| May | 29°C | 25°C | 28°C | 61 mm |
| June | 29°C | 25°C | 29°C | 107 mm |
| July | 29°C | 25°C | 29°C | 129 mm |
| August | 30°C | 26°C | 30°C | 118 mm |
| September | 30°C | 26°C | 30°C | 109 mm |
| October | 29°C | 26°C | 30°C | 108 mm |
| November | 29°C | 25°C | 29°C | 113 mm |
| December | 28°C | 24°C | 28°C | 71 mm |
When to go to St Lucia
What is the best month to visit St Lucia for sun?
For warm, mostly dry days, go February to April, going by our 10-year averages.
What is the hottest month in St Lucia?
September averages 30°C. January is the coolest at 27°C.
When does it rain most in St Lucia?
July, with about 129 mm of rain.
When is the sea warm enough to swim in St Lucia?
all year, when the sea averages 21°C or more.
How we measured this
Daily averages from 2016 to 2025, from the Open-Meteo historical weather archive (ECMWF ERA5 reanalysis); sea temperatures are 2023 to 2025 averages from the Open-Meteo marine archive. Rain is the average monthly total.
Going to St Lucia?
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