Discover French Guiana
Very few tourists make it to this small South American country. It's a shame, because nature in French Guiana is still pure and unspoiled.
September in Cayenne brings very high temperatures, with highs of 32°C (90°F) and nights dropping to 24°C (75°F). It's also the driest month of the year, ideal for those who want to avoid rain.
Our weather planner can help you find worldwide destinations with pleasant weather during this period. September typically offers the best weather for Cayenne.
Pick a month to see the average temperature, rainfall and sunshine in Cayenne - and find the best time to visit.
46-year average (1976-2025)
Based on our historical records, temperatures in Cayenne typically stay consistent throughout September, with daily highs averaging around 32°C (90°F). Nights are warm, with lows around 23°C (73°F).
46-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Browse day-by-day weather records for Cayenne spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Based on 34 years of weather observations in Cayenne between 1992 and 2026, these are the recorded extremes.
Find out more about the weather in French Guiana and which places have the best travel conditions in this month. See all of French Guiana in September →
Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
Warm weather calls for comfortable, breathable clothing in September. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). Rain is likely on several days, so bring a good rain jacket. With water temperatures around 28°C (82°F), swimming conditions are excellent. Pack your swimsuit, goggles, and maybe some water shoes. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Cayenne climate overview or explore weather in French Guiana.
Where to go in September - average daytime high across popular destinations.
Need travel inspiration? Check out our bucket list articles and be inspired.
Discover French Guiana
Very few tourists make it to this small South American country. It's a shame, because nature in French Guiana is still pure and unspoiled.
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