September weather forecast
Cayenne, French Guiana

September in Cayenne, French Guiana, is synonymous with the driest month. Though temperatures remain consistent, the reduced rainfall significantly changes the city's vibes. People enjoy more outdoor activities as sunshine hours peak and rainfall drops to its annual minimum. September graces the month with a scarce 56mm (2.2") of rainfall, marking its classification as the driest month.

Temperature

In Cayenne, September's average high-temperature stands at a still hot 32.1°C (89.8°F), closely related to the preceding month. During September, the temperature is averaged to a low of 22.2°C (72°F) at night.

Rainfall

September is the month with the least rainfall. Rain falls for 7.1 days and accumulates 56mm (2.2") of precipitation.

Sea temperature

In Cayenne, French Guiana, the average seawater temperature in September is 28.5°C (83.3°F).
Note: Water temperatures ranging between 25°C (77°F) and 29°C (84.2°F) are regarded as very warm, making swimming, diving, and similar water activities pleasurable for extended periods.

Daylight

In Cayenne, the average length of the day in September is 12h and 8min.
On the first day of September, sunrise is at 06:22 and sunset at 18:35. On the last day of the month, sunrise is at 06:16 and sunset at 18:21 -03.

Sunshine

With an average of 8.5h of sunshine, September has the most sunshine of the year in Cayenne, French Guiana.

UV index

The months with the highest UV index are January through June, August through November, with an average maximum UV index of 12. A UV Index value of 11, and more, symbolizes an ultimate health vulnerability from exposure to the Sun's UV rays for average individuals.
Note: The maximum daily UV index of 12 in September converts into the following recommendations:
Adopt every vital precaution, unprotected skin and eyes may burn rapidly. Between 10 a.m. and 4 p.m., UV radiation is strongest. Make an effort to avoid direct sunlight during this time, remembering that shade structures may not provide full sun protection. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Directly after swimming or an outdoor workout, generously apply and reapply a broad-spectrum SPF 30+ sunscreen. Be on guard! The reflective nature of sand and water boosts UV exposure.