Last updated: July 31, 2025
Saint Barthélemy boasts a tropical climate characterized by warm temperatures and distinct seasonal variations in rainfall. The maximum temperature peaks at a balmy 29°C (85°F) in October, while an average temperature of 26°C (80°F) ensures a pleasant atmosphere year-round. The coolest month, February, sees temperatures dipping to a comfortable 22°C (72°F). Annual precipitation totals around 801 mm (31.5 in), with the wettest months falling between July and October, where September experiences a notable 22 rainy days. Meanwhile, humidity levels reach their peak in July at 83%, while February offers a drier experience with a minimum of 77%. This idyllic climate makes Saint Barthélemy a prime destination for sun-seekers and nature enthusiasts alike.
Saint Barthélemy enjoys a tropical savanna climate, classified under the Köppen-Geiger system as Aw. This means the island experiences warm temperatures year-round, with distinct wet and dry seasons. The dry season typically spans from December to May, marked by lower humidity and plenty of sunshine, making it the perfect time for beachgoers and water sports enthusiasts. Conversely, the wet season, occurring from June to November, brings increased rainfall and humidity, but still offers warm temperatures, creating a lush, vibrant landscape. With its ideal climate, Saint Barthélemy is a tropical paradise that attracts visitors seeking both adventure and relaxation.
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Saint Barthélemy boasts a delightful tropical climate throughout the year, with temperatures that remain fairly consistent. January to March see comfortable lows around 22-23°C (72-74°F) and average highs of approximately 25-26°C (77-79°F), making it an ideal time for visitors seeking pleasant weather. As the spring turns to summer in April and May, temperatures gradually rise, peaking in June through August, where daily averages reach 27-28°C (81-82°F) and maximums flirt with 29°C (84-85°F). The warmth is accompanied by vibrant island activities, making these months particularly enticing. As autumn sets in from September to November, temperatures remain steady, with averages around 27-28°C (80-82°F), ensuring that warmth lingers even as the year ends. Finally, December ushers in a slight dip, but with averages still at a cozy 26°C (79°F), Saint Barthélemy remains an inviting escape even in the winter months.
Saint Barthélemy experiences a distinct pattern of precipitation throughout the year, with rainfall gradually increasing from January to September. Starting off the year, the islands see relatively low rainfall amounts, averaging around 35 mm in January and February. As the months progress, there is a noticeable rise, peaking in September with a substantial 152 mm of rain, often accompanied by 22 rainy days. August and July also contribute to this wet period, reflecting a wetter summer dynamic. Following September, rainfall begins to taper off, with October and November still receiving noteworthy amounts of 113 mm and 95 mm, respectively, but with fewer rainy days. The transition from the dry to the wet season is quite pronounced, making the latter months of the year a key time for precipitation on the island.
Saint Barthélemy experiences a consistently high level of humidity throughout the year, starting at 77% from January to March. As spring unfolds, a gradual rise to 78% in April and 79% in May signals the approaching summer humidity. By June, the island reaches its peak with 81%, continuing to climb to 83% in July, making for a steamy atmosphere ideal for lounging by the beach. As the summer months progress into August and September, humidity slightly dips to 82% and 80%, respectively, before stabilizing in the fall. Despite a minor decrease to 78% in December, the overall trend reflects a tropical climate where moisture levels remain high, enriching the island's lush landscapes and vibrant marine life year-round.
In Saint Barthélemy, the UV Index showcases a striking trend of intensity throughout the year. Beginning in January, the Index starts at a very high level of 9, necessitating a burn time of only 15 minutes. However, as the months progress into February, it escalates dramatically to an extreme level of 11, and remains at this extreme threshold of 13 from March through September. This prolonged period of intense UV exposure, with a burn time consistently at just 10 minutes, highlights a critical need for sun protection during these months. While October sees a slight dip to 12, the UV levels decline back to 9 in November and December, indicating a seasonal decrease. Overall, visitors and residents alike must stay vigilant during the spring and summer months when the sun's rays are at their most perilous.
UV Risk Categories
Saint Barthélemy basks in abundant sunshine, with hours steadily climbing as the year unfolds. January starts strong with 259 hours, but February sees an impressive jump to 299 hours. The peak sunshine period arrives in the late spring and summer months, where May shines brightest at 363 hours, closely followed by July with 364 hours. As summer fades, sunshine remains generous, with August and September still enjoying over 320 hours. Interestingly, the later months, from October to December, offer a gentle decline, yet still deliver a satisfying 321 to 324 hours of sunshine. Overall, visitors can expect a sun-kissed paradise, particularly in the vibrant months of spring and summer.
In Saint Barthélemy, the likelihood of sunny weather varies significantly throughout the year, showcasing distinct seasonal trends. February and March stand out as the sunniest months, boasting high probabilities of 71% and 72% respectively, perfect for beachgoers. As spring unfolds, April experiences a drop to 47%, hinting at the shift towards the wetter season. However, May regains a respectable 60%, inviting visitors to relish the beautiful Caribbean sunshine before June ushers in a notable decrease to 25%. The summer months of July and August see a modest recovery at 50% and 47%, while the autumn brings back sunny skies, particularly in September, with a 58% chance. The year's end ushers in a return to sunnier weather patterns, peaking once again in November with 67% and maintaining a healthy 65% in December. Overall, Saint Barthélemy offers a delightful range of weather, making it a year-round destination, especially for those who thrive under sunny skies.
Throughout the year in Saint Barthélemy, daylight hours exhibit a captivating rhythm that enhances the island's allure. From January to February, visitors can bask in approximately 11 hours of sunshine, setting a serene tone for the beginning of the year. As March arrives, the daylight extends to 12 hours, inviting more exploration and adventure. The trend continues through April and May, maintaining these longer days, perfect for sun-soaked beach outings. The summer months of June and July peak with a delightful 13 hours of daylight, making for unforgettable late sunsets. As the island transitions into fall, August and September bring a gentle decrease back to 12 hours. Finally, as the year draws to a close in October, November, and December, daylight hours settle back to 11 hours, allowing for cozy evenings under starlit skies. This annual ebb and flow of sunlight not only shapes daily activities but also enriches the vibrant atmosphere of this Caribbean paradise.
The climate of Saint Barthélemy is characterized by a delightful warmth and moderate humidity throughout the year, making it an appealing destination for sun-seekers. With average temperatures hovering around a pleasant 25°C (77°F) in the cooler months of January to March, the heat gradually rises, peaking at an inviting 28°C (82°F) during the summer months. Although July and August boast the highest maximum temperatures reaching 29°C (84-85°F), they also bring increased humidity, reaching up to 83%. Notably, the island experiences its wettest months from September to November, with precipitation occurring on 22 and 19 days respectively. This seasonal shift offers a refreshing contrast to the otherwise sunny disposition. Despite the slight uptick in rainfall, the overall climate remains favorable, allowing visitors to indulge in the island's beauty year-round.