Weather in St Lucia in July

How July compares

July is the 5th warmest month of the year in St Lucia and ranks 60th of 134 destinations we compare for July - see where else is hot in July. Against London's average high of 21.8°C in July, St Lucia is 7.0°C warmer by day and 11.4°C warmer at night.

Daytime and night-time in July

The typical July day in St Lucia peaks at 28.8°C, but that is an average: the warmest 10% of days reach 29.7°C or more. About 100% of days top 25°C and 1 in 20 pass 30°C. Nights average 24.9°C; one night in ten drops to 24.0°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest July day here reached 30.6°C (2020-07-19) and the coldest night 23.4°C (2008-07-17).

Rain in July

Wet (more than 8 rainy days): about 21 days with 1 mm or more, 89 mm in total. Year to year it varies a lot - the wettest July was 2020 with 214 mm, the driest 2015 with 37 mm. Humidity averages 78%, which makes the heat feel heavier than the thermometer suggests.

Sea temperature in July

The sea averages 28.0°C - warm enough to swim (22°c+). Depending on the year it ranges from 27.5°C to 28.5°C. For the warmest sea here, come in September (29.0°C).

Sunshine and daylight

Around 5.8 hours of sunshine a day (estimated from cloud cover), 12.8 hours of daylight: the sun rises about 05:44 and sets about 18:36 local time in mid-July. Average cloud cover is 54%.

Is July 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 days, humid air and little evening cooling

July’s daytime high is around 7°C above London’s, so expect a clear change from a typical British summer. Humidity of 78% adds to the warmth, making loose, breathable clothing more useful than heavy layers. Average night lows sit around 25°C, so evenings offer limited relief; air conditioning is a sensible accommodation priority if you struggle to sleep in heat. Only 5% of days reach 30°C, but that does not make July feel mild. Keep strenuous outdoor plans away from midday, take breaks and carry water. This suits travellers who enjoy sustained warmth better than those who prefer cool evenings after a hot day.

Plan around rain, not an uninterrupted stretch of sun

Rain is the main catch: about 21 days receive at least 1 mm, so wet weather should be part of your plans rather than a surprise. That figure does not mean it rains all day, but it is a reason to avoid a tightly packed outdoor schedule. Sunshine averages about 5.8 hours within 12.8 hours of daylight, leaving scope for time outside without promising clear skies throughout. Pack a light waterproof and something to protect your belongings from rain. July works best if you can rearrange swimming and outdoor time around the conditions; it is less convincing if dependable dry weather is your priority.