Castries, Saint Lucia Climate & Monthly Averages
The climate of Castries
Located in Saint Lucia, Castries experiences a tropical wet-and-dry climate with year-round warmth split between a rainy season and a pronounced dry season. Afternoon temperatures peak near 86°F (30°C) in September and dip to about 81°F (27°C) in January, with around 36.2 inches (920 mm) of precipitation falling across the year.
Climate quick facts
- Hottest month: September - highs near 86°F (30°C)
- Coldest month: January - highs near 81°F (27°C)
- Record high: 91°F (33°C) · Record low: 67°F (19°C) (2015–2024)
- Wettest month: July (24 rainy days) · Sunniest: April (11.8 h sun/day)
- Climate type: tropical wet-and-dry - year-round warmth split between a rainy season and a pronounced dry season
Temperatures through the year
The warmest stretch of the year centers on September. Highs average 86°F (30°C) and overnight lows stay near 77°F (25°C). The coolest month is January, with typical highs of 81°F (27°C) and lows around 73°F (23°C). Based on 2015–2024 weather data, temperatures have reached as high as 91°F (33°C) and dropped as low as 67°F (19°C).
Rain, sun and snow
July is usually the wettest month. It brings about 4.6 inches (116 mm) of rain over 24 days, while April is the driest. April brings the most sunshine, averaging 11.8 hours of sun a day.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 81° | 73° | 18 | 2.2 in | 10.8 h/day | 76% |
| February | 81° | 73° | 13 | 1.8 in | 11.1 h/day | 74% |
| March | 82° | 73° | 15 | 1.9 in | 11.6 h/day | 74% |
| April | 84° | 74° | 12 | 1.5 in | 11.8 h/day | 73% |
| May | 85° | 76° | 13 | 1.9 in | 11.7 h/day | 74% |
| June | 85° | 76° | 19 | 3.3 in | 11.3 h/day | 77% |
| July | 84° | 76° | 24 | 4.6 in | 11.5 h/day | 80% |
| August | 85° | 76° | 23 | 4.2 in | 11.3 h/day | 80% |
| September | 86° | 77° | 22 | 4.5 in | 11.2 h/day | 80% |
| October | 85° | 76° | 21 | 3.9 in | 10.8 h/day | 80% |
| November | 83° | 75° | 21 | 4.4 in | 10.5 h/day | 80% |
| December | 82° | 74° | 17 | 2.2 in | 10.7 h/day | 77% |
Castries month by month
Castries weather in January
January brings highs around 81°F (27°C), lows near 73°F (23°C), about 18 wet days - typically the coldest month of the year in Castries.
Castries weather in February
February brings highs around 81°F (27°C), lows near 73°F (23°C), about 13 wet days.
Castries weather in March
March brings highs around 82°F (28°C), lows near 73°F (23°C), about 15 wet days.
Castries weather in April
April brings highs around 84°F (29°C), lows near 74°F (24°C), about 12 wet days - typically the driest month and the sunniest month of the year in Castries.
Castries weather in May
May brings highs around 85°F (30°C), lows near 76°F (24°C), about 13 wet days.
Castries weather in June
June brings highs around 85°F (29°C), lows near 76°F (24°C), about 19 wet days.
Castries weather in July
July brings highs around 84°F (29°C), lows near 76°F (24°C), about 24 wet days - typically the wettest month of the year in Castries.
Castries weather in August
August brings highs around 85°F (29°C), lows near 76°F (25°C), about 23 wet days.
Castries weather in September
September brings highs around 86°F (30°C), lows near 77°F (25°C), about 22 wet days - typically the hottest month of the year in Castries.
Castries weather in October
October brings highs around 85°F (29°C), lows near 76°F (25°C), about 21 wet days.
Castries weather in November
November brings highs around 83°F (28°C), lows near 75°F (24°C), about 21 wet days.
Castries weather in December
December brings highs around 82°F (28°C), lows near 74°F (24°C), about 17 wet days.
Seasons in Castries
March through May
March through May in Castries runs hot, with daytime highs averaging 84°F (29°C) and nights around 74°F (24°C); expect showers on roughly 40 days across the season. With the humidity factored in, afternoons often feel hotter than the thermometer reads - run the numbers through the humidity and dew point converter to see why.
June through August
June through August in Castries is hot, with daytime highs averaging 84°F (29°C) and nights around 76°F (25°C); expect showers on roughly 66 days across the season.
September through November
September through November in Castries brings hot afternoons, with daytime highs averaging 85°F (29°C) and nights around 76°F (25°C); expect showers on roughly 63 days across the season.
December through February
December through February in Castries brings hot afternoons, with daytime highs averaging 81°F (27°C) and nights around 73°F (23°C); expect showers on roughly 47 days across the season.
Climate questions, answered
What is the average temperature in Castries?
Is Castries hot in summer?
Is Castries cold in winter?
How many rainy days does Castries get in a year?
Best time to visit Castries
The best time to visit Castries is generally January to April and July, when these months combine the driest skies with the most comfortable heat. Daytime temperatures in that window typically sit near 83°F (28°C).
Pack for Castries with lightweight, breathable clothing and strong sun protection for the hot months; a compact umbrella or rain shell - showers are a regular feature; moisture-wicking fabrics to cope with the humidity. Evenings can feel noticeably cooler than afternoons - September nights average 77°F (25°C).
Castries temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.