Weather in Castries

Planning your day in Castries? Check out the freshest weather information: here you will find up-to-date data, forecasts, and useful weather charts.

Castries, the capital of Saint Lucia, boasts a tropical climate characterised by warm and humid weather throughout the year. Average annual temperatures fluctuate only slightly, remaining in a comfortable range from 25°C to 28°C, making the city an attractive destination at any time of the year. Minimum and maximum daily temperatures also demonstrate enviable stability, ensuring pleasant conditions for relaxation.

Although there are no sharp seasonal changes in Castries, two conditional periods can be distinguished. The drier season usually lasts from February to May, when the number of days with precipitation is minimal, though light rains are still possible. From June to November, an increase in the number of days with precipitation is observed, corresponding to the wetter season. It is important to note that even during this period, rains are often short-lived and refreshing, and the total amount of rainfall remains moderate.

Overall, the weather in Castries is predictable and favourable for tourism. High humidity is an integral part of the tropical climate, so light, breathable clothing will be the most comfortable. Regardless of the month of travel, travellers can expect a warm Caribbean Sea and a sunny atmosphere, occasionally interrupted by tropical showers.

The temperature pattern in Castries is distinguished by enviable consistency throughout the year, which is typical for the tropical climate of Saint Lucia. Monthly average temperatures fluctuate within a very narrow range, creating a feeling of eternal summer. The hottest month is usually September, when the average temperature reaches 27.6°C, and daytime highs can rise to 29.3°C. The "coolest" month is considered to be February, with an average temperature of 25.4°C and minimum night-time temperatures around 23.9°C, which is nonetheless a very comfortable figure for a holiday.

Even the conditional division into warmer and less warm periods in Castries is quite symbolic due to minimal temperature fluctuations. The period from May to October can be characterised as the warmest: average daytime temperatures consistently stay above 28°C (for example, in June and August up to 28.8°C, in September up to 29.3°C), and nights remain very warm, with temperatures rarely dropping below 25.4°C (May) – 26.0°C (September). In the so-called "cooler" months, from December to March, the air temperature decreases only slightly. During the day, the thermometer usually shows about 26.9°C (January, February) to 27.5°C (December), and at night it drops to a pleasant 23.9°C (February) – 24.6°C (December). This ensures mild and warm weather all year round.

One of the characteristic features of the climate in Castries is the small difference between day and night temperatures. Daily fluctuations are generally within the range of 2.8°C - 3.3°C (for instance, in January the difference is 2.9°C, and in September it is 3.3°C). This means there are no sharp drops and conditions remain consistently comfortable at any time of day. Such a steady temperature background makes the climate of Castries exceptionally pleasant for those who prefer constant warmth without significant spikes, allowing one to enjoy outdoor leisure both during the day and in the evening.

Precipitation in Castries is an integral part of the tropical climate; however, its distribution throughout the year allows for the distinction of two main periods. Although rains are possible in any month, their intensity and frequency vary noticeably. It should be noted that Castries is rarely subjected to heavy and prolonged downpours. Even in months when more precipitation falls, it predominantly comes in the form of short-lived tropical rains that bring pleasant coolness.

A drier period in Castries is usually observed from February to April. During these months, the least amount of precipitation falls – only about 1 mm per month. February, March, and April are characterised by the lowest rainfall. March and May also stand out with the fewest rainy days – an average of 13 days each. Despite this, even during this period, the probability of rain remains, but the precipitation is generally light and brief.

From June to November, a wetter season arrives in Castries. The amount of precipitation increases, reaching its peak of 4 mm per month from July to November. The highest number of rainy days falls in August – an average of 26 days, followed by July with 25 rainy days. September, October, and November also register 22 rainy days each. It is important to note that even during this period, the total amount of rainfall is small, suggesting that the rains, while frequent, are often not very heavy or prolonged.

Thus, the wettest months in Castries by rainfall amount are July, August, September, October, and November, and by frequency of rains – August and July. The driest months by volume of precipitation are February, March, and April, while March and May differ by having the lowest number of days with precipitation. Snow is absolutely uncharacteristic for Castries due to high temperatures all year round.

When packing your suitcase for a trip to Castries, orient yourself towards typical tropical weather: it is warm here all year round. The basis of your wardrobe should consist of light and breathable fabrics, such as cotton or linen – sundresses, shorts, t-shirts. Do not forget swimwear, sunscreen with high SPF, sunglasses, and a hat for protection against the bright Caribbean sun. For walking around the city and its picturesque surroundings, comfortable footwear, such as sandals or light trainers, is ideal. A light cover-up or sarong may also be useful – both to cover up from the sun and for evening coolness, although evenings here are also very warm.

Although the temperature in Castries remains comfortably high throughout the year, the amount of precipitation varies. From February to May rains happen less often, but a compact umbrella or a light raincoat would not be amiss for complete peace of mind. In the period from June to November, when the probability of precipitation is higher (especially in July and August, when there can be up to 25-26 rainy days per month), these accessories become particularly relevant. Clothing made from quick-drying materials will also be a practical choice. Considering the tropical climate and humidity, do not forget insect repellent. The principle of layering clothing is not as critical here due to constant warmth, however, a light cardigan or stole may be useful in air-conditioned rooms or during rare sea breezes in the evening.