Cayenne weather by month & the best time to visit
French Guiana · beach resort · tropical monsoon climate
The best time to visit Cayenne is September — its sunniest month (Sunshine Score 81/100), with October and August close behind. Cayenne averages about 2,049 hours of sunshine a year. Daytime highs around 29°C / 84°F and roughly 54 mm of rain in September.
When is the best time to visit Cayenne?
For sunshine, the best time to visit Cayenne is September, then October and August. The dullest month is January (63/100, 300 mm of rain). The full month-by-month picture is in the table below.
How sunny is Cayenne?
Cayenne gets a moderate 2,049 hours of sunshine a year. September (81/100) is noticeably better than January (63). It ranks #3 of 3 destinations in French Guiana for annual sunshine, below the national median of 2,290 hours. Rain has a clear season: the wettest stretch, around May, carries about 42% of the annual 2,872 mm.
Sunshine Score by month
| Month | Score | Day high | Night low | Rain | UV | Sea |
|---|---|---|---|---|---|---|
| January | 63 | 27° / 81°F | 24° / 75°F | 300 mm | 8 | 29° / 84°F |
| February | 63 | 27° / 81°F | 24° / 75°F | 264 mm | 9 | 29° / 84°F |
| March | 63 | 28° / 82°F | 24° / 75°F | 250 mm | 9 | 30° / 86°F |
| April | 63 | 28° / 82°F | 25° / 77°F | 369 mm | 9 | 30° / 86°F |
| May | 63 | 28° / 82°F | 25° / 77°F | 504 mm | 8 | 29° / 84°F |
| June | 63 | 28° / 82°F | 25° / 77°F | 334 mm | 9 | 30° / 86°F |
| July | 63 | 28° / 82°F | 24° / 75°F | 217 mm | 10 | 30° / 86°F |
| August | 71 | 28° / 82°F | 25° / 77°F | 109 mm | 11 | 31° / 88°F |
| September | 81 | 29° / 84°F | 25° / 77°F | 54 mm | 12 | 31° / 88°F |
| October | 80 | 30° / 86°F | 25° / 77°F | 58 mm | 11 | 31° / 88°F |
| November | 71 | 29° / 84°F | 25° / 77°F | 110 mm | 10 | 30° / 86°F |
| December | 63 | 28° / 82°F | 25° / 77°F | 303 mm | 8 | 29° / 84°F |
Sea temperature in Cayenne by month
The sea off Cayenne is warmest in August at around 31°C / 88°F, and coolest in January at 29°C / 84°F. The water sits at a comfortable 21°C or warmer roughly all year round. Month-by-month sea-surface temperatures are in the Sea column of the table above.
Nearest destinations
Head-to-head
How Cayenne compares month by month: Cayenne vs Belém · Cayenne vs Macapá · Cayenne vs Georgetown · all comparisons
Cayenne: questions and answers
What kind of destination is Cayenne?
Cayenne is a beach resort in French Guiana with a tropical monsoon climate — the sea reaches 31°C at its warmest and is swimmable (21°C+) year-round.
How many hours of sunshine does Cayenne get a year?
Cayenne gets about 2,049 hours of sunshine a year, at its best around September.
When is the best time to visit Cayenne?
The sunniest time to visit Cayenne is September, when the Sunshine Score peaks at 81/100 (with October and August close behind). Expect daytime highs around 29°C / 84°F.
What is the least sunny month in Cayenne?
January is the least sunny month in Cayenne, scoring 63/100 with about 300 mm of rain.
What is the sea temperature in Cayenne?
The sea in Cayenne ranges from about 29°C (January) to 31°C (August). Month-by-month sea temperatures are on this page.
How strong is the sun in Cayenne?
The typical midday UV index in Cayenne peaks around 12 (extreme) in September, easing to about 8 (very high) in January. Month-by-month midday UV values are in the UV column of the table on this page.
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