Weather in St Lucia in January

How January compares

January is the 12th warmest month of the year in St Lucia and ranks 25th of 134 destinations we compare for January - see where else is hot in January. Against London's average high of 7.4°C in January, St Lucia is 19.6°C warmer by day and 21.3°C warmer at night.

Daytime and night-time in January

The typical January day in St Lucia peaks at 27.0°C, but that is an average: the warmest 10% of days reach 28.0°C or more. About 99% of days top 25°C. Nights average 23.5°C; one night in ten drops to 22.5°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest January day here reached 29.1°C (2010-01-04) and the coldest night 20.4°C (2020-01-27).

Rain in January

Wet (more than 8 rainy days): about 13 days with 1 mm or more, 36 mm in total. Year to year it varies a lot - the wettest January was 2005 with 114 mm, the driest 2016 with 15 mm. Humidity averages 74%.

Sea temperature in January

The sea averages 27.0°C - warm enough to swim (22°c+). Depending on the year it ranges from 26.6°C to 27.3°C. For the warmest sea here, come in September (29.0°C).

Sunshine and daylight

Around 7.1 hours of sunshine a day (estimated from cloud cover), 11.3 hours of daylight: the sun rises about 06:32 and sets about 17:55 local time in mid-January. Average cloud cover is 37%.

Is January a good time to visit St Lucia?

It is a reasonable choice: hot days but expect showers. The best months for St Lucia on our scoring are February, March, January; months averaging 25°C or more: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec.

Hot enough for swimming, without extreme daytime heat

Average highs of 27°C make January suitable for travellers who want heat without temperatures regularly pushing into the thirties. Almost every day reaches 25°C, so pack mainly light clothes rather than planning for cool daytime weather. Humidity averages 74%, which can make the warmth feel heavier, particularly when you are active; leave room for shade and an easier pace at midday. Nights average 23.5°C, so evenings remain warm rather than offering a sharp cool-down. With the sea at 27°C, swimming is a strong reason to go then. January suits a beach-and-swim holiday better than a trip built around staying cool while active.

Expect sunshine, but leave room for rain

January brings about 7.1 hours of sunshine within 11.3 hours of daylight, giving you useful time for outdoor plans without implying clear skies all day. Rain falls on about 13 days, so a completely dry holiday is not a sensible expectation. That does not mean those days are washouts, but it does make flexible timing more useful than a tightly packed outdoor schedule. Take a lightweight waterproof and keep something suitable for wet weather available rather than relying entirely on sunshine. If your main aim is warmth and swimming, the rain is a manageable trade-off; if uninterrupted sunshine is essential, January comes with a catch.