Last updated: August 31, 2025
In September, Vieques, Puerto Rico, experiences warm and humid conditions, characterized by a maximum temperature reaching 31°C (89°F) and an average of 28°C (82°F). The island’s minimum temperature hovers around 25°C (77°F), providing a pleasantly warm atmosphere. However, this month marks a significant increase in precipitation, with 154 mm (6.0 in) of rain spread over 24 days, contributing to the high humidity level of 79%. Visitors should prepare for tropical showers while enjoying the vibrant beauty of this Caribbean paradise.
In September, Vieques, Puerto Rico, bathes in warm tropical vibes with temperatures that reflect the peak of summer. The month presents a minimum temperature of 25°C (77°F), rising to an average of 28°C (82°F), and can peak at a sweltering 31°C (89°F). As the island transitions from the summer months, both the highs and lows show a slight increase compared to previous months, indicating the lingering warmth. September's balmy conditions invite beachgoers to enjoy the sandy shores and vibrant ocean, while the evenings remain comfortably warm, perfect for outdoor dining under the stars. The consistency of warmth highlights Vieques' allure as a year-round tropical getaway.
September in Vieques, Puerto Rico, marks a significant upswing in precipitation, with an impressive 154 mm (6.0 in) of rainfall falling over 24 days. This marks the peak of the rainy season, reflecting a trend of increasing moisture that begins in the summer months, as both July and August also exhibit heavy rainfall, with 110 mm (4.3 in) and 111 mm (4.4 in), respectively. The consistent pattern of precipitation in September sets the stage for the subsequent wet months of October and November, though with a gradual decrease in rainfall amounts. As the island transitions toward fall, September's abundant rains foster lush landscapes, contributing to the vibrant natural beauty that Vieques is known for.
In September, Vieques, Puerto Rico, experiences a humidity level of 79%, marking a slight decrease from the elevated 80% recorded in both July and August. The humid conditions that characterize the summer months gradually transition into the milder autumn climate. Overall, humidity levels in Vieques tend to oscillate between 74% and 80% throughout the year, with the peak observed in mid-summer. As the year progresses toward autumn, the humidity begins to stabilize, offering a more comfortable environment while still retaining the island's characteristic tropical feel. This trend highlights the resilience of Vieques' climate, balancing warmth and moisture seamlessly.
In September, Vieques, Puerto Rico, experiences an exceptional UV Index of 14, placing it firmly in the extreme exposure category. This is part of a consistent trend seen throughout the summer months, where the UV Index remains high. From June to August, the UV levels hovered at a notable 13, but as September rolls in, sun-seekers must be especially cautious, as the risk of skin damage is amplified with a swift 10-minute burn time. The only reprieve comes later in the year; by October, the index drops to 12, still within the extreme category but offering a slight relief. As the sun shines relentlessly in September, it’s crucial to stay informed about the UV Index and practice sun safety while exploring this beautiful island. For more detailed information, check out the Vieques UV Index.
UV Risk Categories
In September, Vieques, Puerto Rico, enjoys a delightful 318 hours of sun, continuing the trend of abundant sunshine that has captivated visitors throughout the summer months. Following an impressive peak in May with 357 hours, sunlight gradually tapers off, yet September still boasts a generous amount compared to the start of the year. This month serves as a bridge between the intense summer glow and the slightly cooler fall, offering travelers a perfect backdrop for beach days and outdoor adventures. With days still bright and warm, September in Vieques promises both radiant skies and the tranquil beauty that makes this island a sought-after destination.
As summer gives way to autumn, September in Vieques, Puerto Rico, showcases a slightly optimistic chance for sunny skies, with a likelihood of 49%. This places it favorably within the spectrum of yearly weather patterns, especially when compared to the preceding summer months, which experience lower sunshine probabilities, dropping to just 23% in June and hovering around the mid-30s in July and August. While September's numbers hint at a return to brighter days, they remain closely aligned with October's 50%, suggesting that the charm of Vieques continues into the fall. Travelers can look forward to a balanced blend of sun and clouds, making September a promising time for enjoying the island's natural beauty.
In September, Vieques enjoys a delightful 12 hours of daylight, continuing the trend of ample sunshine that characterizes the preceding summer months. After peaking at 13 hours in June and July, the daylight duration begins to settle, maintaining a balance that ensures plenty of time for both adventure and relaxation. This pattern of gradually decreasing daylight extends into the fall, with October also providing 11 hours of sunlight. Overall, September marks a transitional period, where the days remain luxuriously long, offering visitors and residents alike the perfect opportunity to immerse themselves in the island's vibrant culture and stunning natural beauty.
In September, Vieques, Puerto Rico, experiences its lightest winds of the year, with an average speed of just 3.8 m/s (9 mph). This marks a noticeable decline from the higher gusts of the summer months, where July and August boast winds of 6.1 m/s (14 mph) and 5.4 m/s (12 mph) respectively. As autumn approaches, the gentler breezes provide a serene backdrop for visitors seeking a tranquil escape, contrasting sharply with the robust winds of earlier months. This transitional period signals a shift towards calmer weather, making September an ideal time for reflection and relaxation on the stunning shores of Vieques.
Weather in Vieques varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Vieques, focusing on differences in temperature, rainfall, humidity, and UV levels.
September typically experiences warmer temperatures compared to January, with daily averages reaching around 28°C (82°F) and maximums peaking at 31°C (89°F). In contrast, January sees milder averages of 25°C (77°F) and maximum temperatures of 29°C (84°F). Additionally, September is significantly wetter, receiving 154 mm (6.0 in) of rainfall over 24 days, while January has a much drier climate with only 49 mm (1.9 in) over 15 days. Despite the slight drop in humidity from September's 79% to January's 76%, both months maintain a tropical feel. For more detailed insights, you can check this link: Vieques weather in January.
When comparing September and February weather, notable differences emerge. September features warmer temperatures with a minimum of 25°C (77°F) and an average of 28°C (82°F), reaching a high of 31°C (89°F). The month also experiences significant rainfall, totaling 154 mm (6.0 in) over 24 days, accompanied by a humidity level of 79%. In contrast, February presents a cooler climate, with minimum temperatures around 21°C (71°F) and a comfortable average of 25°C (77°F), peaking at 28°C (83°F). Additionally, February is drier, receiving only 52 mm (2.1 in) of precipitation across 19 days, and slightly lower humidity at 75%. For a more detailed look at February weather, check out Vieques weather in February.
In September, the weather is typically warmer and more humid, with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 31°C (89°F) and an average of 28°C (82°F). The month also sees significant rainfall, with about 154 mm (6.0 in) of precipitation over 24 days, making it a notably wet period. In contrast, March offers milder conditions, featuring temperatures that range from a minimum of 22°C (72°F) to a maximum of 28°C (83°F) and an average of 25°C (77°F). Additionally, March experiences much lower rainfall, totaling 63 mm (2.5 in) across 18 days, along with slightly lower humidity at 74%. For a more detailed overview of March weather in Vieques, visit Vieques weather in March.
When comparing the weather in September and April, September tends to be warmer and more humid. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (89°F), with an average temperature of 28°C (82°F). The month is characterized by significant rainfall, totaling 154 mm (6.0 in) over 24 days, which contributes to a humidity level of 79%. In contrast, April offers slightly cooler temperatures, with a minimum of 22°C (73°F) and a maximum of 29°C (85°F), averaging 26°C (78°F). Precipitation during this month is considerably lower, amounting to 55 mm (2.2 in) over 17 days, along with a humidity level of 75%. For a more detailed look at the weather in April, you can check out Vieques weather in April.
In comparing the weather between September and May, it is evident that September tends to be warmer, with an average temperature of 28°C (82°F) compared to May’s average of 26°C (80°F). While both months experience high humidity, September's humidity level is slightly increased at 79%, compared to May's 75%. Additionally, September is significantly wetter, receiving 154 mm (6.0 in) of precipitation over 24 days, while May has only 74 mm (2.9 in) over 21 days. For more details on May’s weather, you can visit Vieques weather in May.
In comparing the weather between September and June, both months display warm temperatures, but September tends to be slightly warmer overall. September features a minimum temperature of 25°C (77°F) and an average of 28°C (82°F), peaking at 31°C (89°F), while June has slightly lower readings with a minimum of 24°C (76°F) and a maximum of 30°C (87°F). Precipitation is notably higher in September, accumulating 154 mm (6.0 in) over 24 days, compared to June’s 69 mm (2.7 in) over just 21 days. Humidity levels are also a bit higher in September at 79%, compared to 77% in June. For more detailed information on weather conditions in June, you can check Vieques weather in June.
When comparing the weather in September to that of July, it's evident that both months share similar average temperatures, with September showing a slight increase in the maximum temperature at 31°C (89°F) compared to July’s 30°C (87°F). However, September is noticeably wetter, with 154 mm (6.0 in) of precipitation over 24 days, while July experiences less rainfall at 110 mm (4.3 in) for the same number of days. Humidity levels remain high in both months, but September's average humidity is slightly lower at 79% versus July's 80%. For more detailed information on July weather, visit Vieques weather in July.
In comparing the weather between September and August, we notice that both months have similar temperature ranges, with minimums at 25°C (77°F), averages at 28°C (82°F), and maximums approaching 31°C (89°F in September and 88°F in August). However, September experiences a higher level of precipitation, totaling 154 mm (6.0 in) over 24 days, compared to August's 111 mm (4.4 in) over the same number of days. Additionally, September's humidity is slightly lower at 79%, while August holds a marginally higher average of 80%. For more detailed information on August's specific weather conditions, you can refer to this link: Vieques weather in August.
In September, temperatures remain quite warm, with a minimum of 25°C (77°F) and an average of 28°C (82°F), peaking at a high of 31°C (89°F). The month is also characterized by substantial rainfall, totaling 154 mm (6.0 in) across 24 days, accompanied by high humidity levels at 79%. In contrast, October sees slightly cooler temperatures, with a minimum of 24°C (76°F) and an average of 27°C (82°F), while still reaching a maximum of 31°C (87°F). Rainfall decreases to 140 mm (5.5 in) over 22 days, and humidity is marginally lower at 78%. For more specific details on October weather patterns, check out Vieques weather in October.
September and November exhibit notable differences in weather patterns. In September, temperatures are slightly higher, with an average of 28°C (82°F) and maximums reaching 31°C (89°F), while November experiences a cooler average of 27°C (80°F) and maximums of 30°C (86°F). Precipitation in September is significantly greater, totaling 154 mm (6.0 in) over 24 days, compared to November's 112 mm (4.4 in) across 21 days. Humidity remains similar, with September at 79% and November dipping slightly to 78%. For more specific insights, you can refer to Vieques weather in November.
In September, the weather is generally warmer with average temperatures peaking at 31°C (89°F) and a higher humidity level of 79%. The month also sees significant rainfall, totaling 154 mm (6.0 in) over 24 days. In contrast, December brings milder conditions, with average temperatures dropping to 26°C (79°F) and slightly lower humidity at 76%. Additionally, precipitation decreases to 68 mm (2.7 in) over 21 days, making for a drier transition into the winter months. For more details, you can explore Vieques weather in December.
As September arrives in Vieques, it ushers in a shift in weather patterns characterized by warmer temperatures and a notable increase in humidity. This tropical paradise experiences its fair share of rainy days, making the month one of the wettest of the year. While the average temperature remains inviting, the elevated precipitation introduces a lush vibrancy to the island, perfect for those who appreciate a verdant landscape. Travelers can expect to enjoy the vibrant scenery as they navigate occasional showers, making September a unique time to experience the beauty and tranquility of Vieques. For a deeper dive into the weather nuances of this enchanting island, explore the detailed information in the Vieques Climate section.