St Lucia weather in August

St Lucia averages 30°C by day and 26°C at night in August, with the sea at 30°C and about 118 mm of rain in the month.

Day

30°C

Night

26°C

Sea

30°C

Rain

118 mm

Flight from London

8½h

What August feels like

August is hot in St Lucia: proper beach weather.

The sea is warm at 30°C: comfortable for long swims.

Expect some rainy spells: about 118 mm falls in the month.

That is 7°C warmer than an average August day in London.

Of the 56 sun destinations we track, St Lucia is the #35 warmest in August.

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Want it warmer in August?

These are hotter than St Lucia this month for at most an hour and a half more flying:

St Lucia weather by month

August is highlighted. Compare with July and September, or see the full year in St Lucia.

MonthDayNightSeaRain
January27°C24°C28°C70 mm
February27°C24°C27°C54 mm
March28°C24°C27°C55 mm
April29°C25°C28°C45 mm
May29°C25°C28°C61 mm
June29°C25°C29°C107 mm
July29°C25°C29°C129 mm
August30°C26°C30°C118 mm
September30°C26°C30°C109 mm
October29°C26°C30°C108 mm
November29°C25°C29°C113 mm
December28°C24°C28°C71 mm

St Lucia in August: quick answers

Is St Lucia hot in August?

August is hot in St Lucia: proper beach weather. Average highs are 30°C and lows 26°C.

Can you swim in St Lucia in August?

The sea is warm at 30°C: comfortable for long swims.

Does it rain in St Lucia in August?

Expect some rainy spells: about 118 mm falls in the month.

What is the warmest month in St Lucia?

September, at an average high of 30°C. The coolest is January at 27°C.

How long is the flight to St Lucia from the UK?

About 8½h direct from London, estimated from the 6,769 km distance. Check your airline for exact times.

Still choosing? See where is hot in August for every destination ranked by temperature, sea and flight time.

How we measured this

Averages of every day in August from 2016 to 2025, from the Open-Meteo historical weather archive (ECMWF ERA5 reanalysis). Sea temperature is the 2023 to 2025 average from the Open-Meteo marine archive. Rain is the average monthly total. Reanalysis describes an area about 25 km across, so sheltered resorts can run a degree or two warmer. Flight time is a distance-based estimate from London Heathrow.

Planning St Lucia in August?

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