September weather forecast
Apatou, French Guiana

September witnesses a substantial drop in rainfall to 26mm (1.02"), the lowest observed in Apatou across the year. Due to lesser cloud cover, the city experiences the highest average sunshine hours, revealing the city under clearer skies. The level of humidity, in line with the fall in rainfall, severely drops, reducing the moisture content in the atmosphere. Winds pick up slightly, ensuring the weather remains pleasant despite less rain. As the dry season fully sets in, September's climate provides ample opportunities to enjoy Apatou's natural beauty without the constant downpour.

Temperature

Apatou greets September with an average high-temperature of a still tropical 32.7°C (90.9°F), marking a slight deviation from the preceding month. In Apatou, an average low-temperature of 22.5°C (72.5°F) is recorded during September nights.

Heat index

The heat index value during September is evaluated at a burning hot 47°C (116.6°F). Keep alert: Heat cramps and heat exhaustion are probable. Heatstroke is a potential danger with continued physical activity.
It is important to note that the heat index values are for shaded areas and light wind scenarios. Exposure to the direct sun might augment heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', combines air temperature and relative humidity to represent a human perceived temperature equivalent. The influence of weather is personal, with varied individuals experiencing it differently due to differences in body mass, stature, and physical exertion levels. Being aware that direct sunlight can impact the felt heat might mean an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially vital to children. Juveniles are regularly less conscious of the need to recuperate and rehydrate. Thirst is a tardy symptom of dehydration - hydration, especially during lengthy physical activities, should be maintained.
To offset high temperatures, the human body releases sweat which, upon evaporation, cools it down. An elevated level of relative humidity hinders evaporation, leading to decreased heat elimination from the body, inducing a sensation of excess heat. Heat-related challenges, like dehydration, can be anticipated when body heat isn't managed effectively.

Humidity

The average relative humidity in September is 79%.

Rainfall

In September, the rain falls for 11.5 days. Throughout September, 26mm (1.02") of precipitation is accumulated. In Apatou, during the entire year, the rain falls for 253 days and collects up to 878mm (34.57") of precipitation.

Daylight

In Apatou, the average length of the day in September is 12h and 9min.
On the first day of the month, sunrise is at 06:30 and sunset at 18:43. On the last day of September, sunrise is at 06:24 and sunset at 18:29 -03.

Sunshine

September has the most sunshine of the year, with an average of 9.1h of sunshine.

UV index

The months with the highest UV index in Apatou are July through November, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV radiation for the average person.
Note: A daily high UV index of 7 in September leads to these guidelines:
Skirt overexposure. People with light complexions might get scorched in under 20 minutes. UV radiation from the Sun is most intense between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.