Last updated: August 21, 2025
September in Cayenne, French Guiana presents a warm and humid atmosphere, with maximum temperatures peaking at 32°C (90°F) and an average of 28°C (82°F). The warmth is accompanied by minimum temperatures around 24°C (76°F), creating a tropical environment perfect for those who enjoy heat. However, be prepared for occasional rainfall, as the month sees an average of 56 mm (2.2 in) of precipitation over 12 days, resulting in a humidity level of 79%. These conditions contribute to the lush greenery that characterizes this beautiful locale.
In September, temperatures in Cayenne, French Guiana begin to rise as the region transitions deeper into the warm season. With a minimum temperature of 24°C (76°F) and an average of 28°C (82°F), the days are increasingly inviting. The maximum peaks at 32°C (90°F), matching the warmest temperatures seen in the prior month of August. This pattern reflects a steady trend of warmth that characterizes the months leading into the end of the year, as Cayenne enjoys tropical weather that maintains a delightful allure for those seeking adventure in its vibrant landscape. Overall, September embraces a climate that balances warmth with the unmistakable charm of the tropics.
September in Cayenne, French Guiana, marks a notable shift in precipitation patterns, as the rainfall drops to just 56 mm (2.2 in), the lowest amount recorded for the year. This decrease is accompanied by a significant reduction in rainy days, with only 12 days of precipitation compared to the heavier downpours of the preceding months. Historically, September serves as a transitional period following the peak rainfall in May and June, offering a brief respite before the wet season regains momentum in October. As the air turns drier and more stable, this month provides a welcome interlude, indicative of the dynamic climate that characterizes the region.
In September, humidity in Cayenne, French Guiana, registers at a comfortable 79%, reflecting a slight drop from the humid peak of 87% experienced in June. This month stands out among its neighbors, showcasing a more moderate level compared to the consistently elevated readings from the summer months, particularly August's 80% and July's 81%. The trend over the year indicates a gradual increase in humidity as the months progress, particularly in the latter half, with November and December reaching 85% and 84%, respectively. September serves as a transitional phase, hinting at the approaching humidity that characterizes the end of the year while still allowing for a brief respite in the tropical climate.
In September, Cayenne, French Guiana, experiences a UV Index of 13, classified in the extreme exposure category, which signals an urgent need for sun protection. This consistent index mirrors the pattern seen throughout the year, with only slight fluctuations—January and February peak at 14, while March and April reach a maximum of 16. From May onwards, the UV levels hold steady between 12 and 14, maintaining that all-too-important 10-minute burn time reminder. As the tropics continue to bask in radiant sunshine, safeguarding your skin with appropriate measures remains essential. For more information about the UV Index in Cayenne, visit Cayenne UV Index.
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September in Cayenne, French Guiana, brings a delightful blend of warmth and brightness, as the region basks in an impressive 337 hours of sunshine. This month continues the trend of abundant sunlight that begins in the summer, with August leading the pack at 346 hours. Following July's peak of 331 hours, September showcases that the sunny streak remains strong, even as the days begin to shorten. With the sun consistently gracing the skies, it's no surprise that Cayenne emerges as an ideal spot for sun-seekers, right before transitioning into the more moderate sunlight of October at 342 hours. The sustained warmth and light create a vibrant atmosphere, perfect for both locals and visitors alike to enjoy the splendor of this tropical paradise.
In Cayenne, French Guiana, the likelihood of sunny weather in September stands at an encouraging 45%. This marks a significant increase from the earlier months, where the sun shares the sky less frequently, particularly in the wetter season of May and April, when the chances plummet to 9% and 11%, respectively. As the year progresses into late summer, August showcases a promising 41% chance of sun, setting the stage for September’s radiant embrace. This upward trend continues into the early fall months, suggesting that September not only offers a reprieve from the heavy rains but also presents one of the best opportunities for sun seekers in the region.
In Cayenne, French Guiana, the month of September offers a delightful consistency in daylight, boasting approximately 12 hours of sunshine each day. As the year progresses, daylight duration remains steady from March through September, highlighting a period of ample sunlight that supports the vibrant local flora and fauna. Following this shining stretch, the daylight begins to wane, tapering to 11 hours in October and continuing through the end of the year. This rhythmic cycle of daylight not only shapes daily life but also invites residents and visitors alike to revel in the beauty of the tropics throughout the year.
As September rolls in to Cayenne, French Guiana, the air begins to embrace a gentle calm, with average wind speeds dipping to 3.2 m/s (7 mph). This marks a continuation of the lower wind trends seen from July through August, where the region experiences its most tranquil breezes. In fact, the winds have steadily decreased since the year’s peak in February, when they reached 6.0 m/s (14 mph). September’s softness offers a soothing contrast to the more vigorous gusts in the earlier months, inviting residents and visitors alike to relish the stillness before a slight uptick in winds returns in October. Overall, the shifting patterns of the September winds highlight a seasonal ebb, perfectly framing the lush beauty of the region.
Weather in Cayenne varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Cayenne, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is generally warm and relatively dry, with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 32°C (90°F) and an average of 28°C (82°F). However, the month does see around 56 mm (2.2 in) of precipitation spread over 12 days, and humidity levels are around 79%. In contrast, January experiences cooler temperatures, with a minimum of 23°C (74°F), an average of 26°C (79°F), and a maximum of 29°C (84°F). This month is also much wetter, with 225 mm (8.9 in) of rainfall occurring over 23 days, while humidity remains slightly lower at 78%. For more detailed information, you can check Cayenne weather in January.
In comparing the weather of September and February, both months experience relatively warm temperatures, with September averaging slightly higher at 28°C (82°F) compared to February's 26°C (79°F). However, February sees significantly more rainfall, with precipitation totaling 189 mm (7.5 in) over 24 days, whereas September has only 56 mm (2.2 in) spread over 12 days. Humidity levels are quite close, with September being slightly higher at 79% compared to February's 76%. For more detailed insights into February weather, you can visit Cayenne weather in February.
When comparing the weather in September and March, both months feature warm temperatures, but March tends to be slightly cooler overall. In September, daily highs can reach up to 32°C (90°F), while March's maximum temperature is around 30°C (86°F). Additionally, September experiences less rainfall, with 56 mm (2.2 in) spread over 12 days, compared to March, which sees a significant increase in precipitation at 196 mm (7.7 in) over 25 days. Humidity levels are relatively similar, with September at 79% and March at 76%. For more detailed insights into March weather, you can visit Cayenne weather in March.
September and April exhibit quite different weather patterns. In September, temperatures are generally warmer, with an average of 28°C (82°F) and maximum highs reaching up to 32°C (90°F). The month sees relatively moderate precipitation, totaling 56 mm (2.2 in) over about 12 days, accompanied by a humidity level of 79%. In contrast, April experiences slightly cooler temperatures, averaging 26°C (80°F) with maximums of 29°C (85°F), but is significantly wetter, with precipitation reaching 390 mm (15.4 in) across 27 days and a similar humidity level of 77%. For a more detailed look at the weather patterns in this month, visit Cayenne weather in April.
When comparing the weather in September and May, one can notice several key differences. September tends to be slightly warmer with average temperatures peaking at 28°C (82°F) and maximums reaching 32°C (90°F). In contrast, May has a marginally cooler average temperature of 26°C (80°F) and a maximum of 30°C (86°F). However, May is significantly wetter, experiencing a whopping 576 mm (22.7 in) of precipitation over 30 days, compared to September's 56 mm (2.2 in) over just 12 days. Both months showcase high humidity levels around 79%-78%, making the atmosphere feel warm and muggy. For more detailed insights on May weather, check out Cayenne weather in May.
September and June present distinct weather characteristics. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 32°C (90°F), with an average of 28°C (82°F). The month experiences significant humidity at 79% and moderate precipitation of 56 mm (2.2 in) over 12 days. In contrast, June sees slightly cooler temperatures, with a minimum of 23°C (75°F) and a maximum of 30°C (86°F), averaging 26°C (79°F). However, June is notably wetter, receiving 433 mm (17.1 in) of rain over an extended 29 days, contributing to a higher humidity of 87%. For more details, visit Cayenne weather in June.
In comparing the weather of September and July, we see that September generally experiences slightly higher temperatures, with averages around 28°C (82°F) compared to July's 26°C (80°F). Both months have a minimum temperature of 24°C (75°F/76°F), but July tends to be wetter, receiving 269 mm (10.6 in) of precipitation over 29 days, while September has only 56 mm (2.2 in) across 12 days. Humidity remains relatively high in both months, with September at 79% and July at 81%. For a more detailed look at the conditions in July, you can visit Cayenne weather in July.
In comparing the weather between September and August, both months experience similar warm temperatures, with September having a slightly higher average temperature of 28°C (82°F) compared to August's 27°C (81°F). However, September sees a reduction in overall precipitation, with 56 mm (2.2 in) of rain over 12 days, while August has a higher rainfall total of 92 mm (3.6 in) over 18 days. Additionally, humidity levels remain relatively consistent, with September at 79% and August at 80%. For more details on August's weather, you can visit Cayenne weather in August.
September and October exhibit similar temperature ranges, with both months averaging around 28°C (82°F) and peaking at 32°C (90°F). However, October sees a slight increase in both minimum temperature, rising to 25°C (77°F), and precipitation, totaling 59 mm (2.3 in) across 16 days, compared to September's 56 mm (2.2 in) over 12 days. Additionally, October maintains a slightly higher humidity level at 80%, compared to September's 79%. For more detailed insights, check out Cayenne weather in October.
In September, the weather is warm with temperatures averaging around 28°C (82°F), peaking at 32°C (90°F), while experiencing a fair amount of humidity at 79%. The month sees relatively moderate rainfall at 56 mm (2.2 in) across 12 days. In contrast, November brings slightly cooler average temperatures of 27°C (81°F), with a maximum of 31°C (88°F). However, it is significantly wetter, with precipitation reaching 204 mm (8.0 in) over 24 days and a rise in humidity to 85%. For more detailed insights, check out Cayenne weather in November.
In September, the weather is generally warm, with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 32°C (90°F), averaging around 28°C (82°F). The month experiences about 56 mm (2.2 in) of precipitation over 12 days, and humidity levels sit at around 79%. In contrast, December sees a slight decrease in average temperature, with minimums still at 24°C (75°F) and maximums reaching 30°C (86°F), averaging 26°C (79°F). However, the humidity rises to 84%, and the month is significantly wetter, recording 349 mm (13.7 in) of precipitation over 29 days. For a detailed look at December's climate, visit Cayenne weather in December.
As September unfolds in Cayenne, it brings a unique blend of warmth and moisture, distinguishing it from other months. With average temperatures hovering around 28°C (82°F), it offers a sultry atmosphere, complemented by high humidity levels that reach up to 79%. Precipitation is notable this month, with 12 wet days contributing to a total of 56 mm (2.2 in) of rain, making September one of the wetter times of the year. While the warmth is consistent, the frequent showers provide a refreshing respite from the heat, setting September apart in the tropical climate spectrum. For a deeper look into the nuances of Cayenne's weather throughout the year, visit Cayenne Climate.