Average TempDay 29°C Night 25°C
St Lucia has a typically tropical Caribbean climate, with lots of sun and maximum daily average temperatures ranging from 29°C to 31°C throughout the year. Like its neighbouring islands, St Lucia has a dry season and a wet season. The dry season runs from December to May and is the busiest time of year, when humidity and rainfall are at their lowest; the wet season from June to November often has heavy showers and sometimes thunderstorms, which help give the island its lush interior. Despite the wetter weather in the second half of the year, the risk of hurricanes remains relatively low and there’s a daily average of 7 to 8 hours of sunshine year-round.
Here’s our month-by-month guide to St Lucia’s weather and climate.
St Lucia in January is perfect for grabbing some winter sun. Rainfall is much lower than during the autumn months and temperatures can get up to around 29°C. Thanks to the northeasterly trade winds you can expect a cooling breeze in January and February, which helps reduce the sun’s heat.
If you’re not sure when to go to St Lucia but don’t want it too hot, February is one of the driest and least humid times of the year. It’s similar to January, with consistently warm temperatures and an average of 7 sunshine hours per day but even less rainfall (a monthly average of just 56mm). Although you can see the majestic Pitons all year, the low humidity makes this a good month for a moderately easy guided hike up Gros Piton.
The dry and sunny St Lucia weather plus the lowest average monthly rainfall of the year make March a great choice. Bear in mind though that the island will be busier during this time, with higher prices for hotels and flights especially around the Easter holidays.
April is the end of the high season. The temperature in St Lucia creeps up to around 30°C and average sunshine increases from 7 to 8 hours per day. The best time for swimming in St Lucia is in April and May when water temperatures are warmest.
May represents the shoulder season before the wet season begins. It marks the start of a hotter St Lucia climate and gradually increasing humidity into the summer months. You’re likely to have relatively low rainfall and up to 8 hours of sunshine per day like in April but with lower prices than the previous spring months, so it’s a good time to go. Visit in the first half of the month to enjoy the St Lucia Jazz Festival – a week-long celebration of Jazz, R&B and Calypso music.
It’s now officially the start of the wet season in St Lucia, with a noticeable spike in humidity. Rainfall increases sharply by the end of the month compared to May, doubling to an average of around 140mm. But June is also good value – there’s lots of consistent sunshine to enjoy, without the summer holiday crowds. The highest wind speeds of any month also help take the edge off the heat.
St Lucia weather in July is similar to June – the humidity and temperatures tend to remain consistent with the previous month, although there’s a little more rainfall on average. If you go in the middle of July, you’ll be able to experience St Lucia’s lively and colourful Carnival in the streets of Castries. Prices may be higher during this period.
For travellers considering when to visit St Lucia, August is one of the hottest and sunniest months of the year with maximum daily average temperatures breaking 31°C. The amount of rainfall is very similar to July, but humidity is now at its highest until November – you’re more likely to feel it due to the considerable drop in wind speeds.
It’s the middle of the wet season and the risk of hurricanes is highest during September and October. There’s plenty of glorious sunshine with temperatures reaching up to 31.5°C, but wind speeds are at a yearly low so it can get humid. It may be too muggy for a full-on outdoorsy holiday, but that shouldn’t discourage you from sunbathing.
October in St Lucia can get fairly wet – the average of 224mm of rainfall is significantly higher than any other month. That said, there’s still an average of 8 hours of sunshine per day, and intermittent showers can help you cool down during the hot weather. The best time to go to St Lucia for whale watching is from October to February.
The wet season comes to an end in November, so even though rain is likely you can expect the frequency and intensity of the showers to gradually decrease. Temperatures remain high (the maximum daily average is around 30.5°C), and for lower prices outside of the school holidays this is a good time of year to visit St Lucia.
The high season begins in December, with humidity and rainfall tailing off compared to the autumn months. Thanks to the increase in wind speeds during winter, nights become cooler and there’s a pleasant breeze during the day; excellent water visibility means now until April is the best time to visit St Lucia for snorkelling. Be prepared for lower hotel availability and higher flight prices, especially during the festive season.