September weather forecastFlèche, French Guiana

September

Weather in September

September, the first month of the autumn in Flèche, is still a tropical month, with an average temperature fluctuating between 32.7°C (90.9°F) and 22.5°C (72.5°F).

Temperature

At the start of September, Flèche's average high-temperature reaches a still hot 32.7°C (90.9°F), subtly different from the preceding month. An average low-temperature of 22.5°C (72.5°F) is expected in Flèche during September.

Heat index

The heat index value for September is appraised at a life-threatening hot 47°C (116.6°F). Stay on guard: Heat exhaustion and heat cramps are predicted. Ongoing effort can cause heatstroke.
One should consider that heat index numbers are for shaded settings and light wind. A rise of up to 15 Fahrenheit (8 Celsius) degrees in the heat index could result from direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', evaluates the perceived heat by adding the effect of moisture in the air. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. Direct exposure to sun rays can potentially augment the heat sensation, elevating the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young children typically face greater hazards than adults because they do not sweat as much. Their larger skin surface in comparison to their little bodies and the high heat production from their active nature compounds their vulnerability.
To achieve cooling, the human body employs perspiration, relying on the subsequent evaporation of sweat. An elevated level of relative humidity hinders evaporation, leading to decreased heat elimination from the body, inducing a sensation of excess heat. When the body's heat gain surpasses its removal capacity, body temperature starts to climb, leading to potential heat-related ailments.

Humidity

In September, the average relative humidity is 79%.

Rainfall

In September, in Flèche, the rain falls for 11.5 days. Throughout September, 26mm (1.02") of precipitation is accumulated. Throughout the year, in Flèche, there are 253 rainfall days, and 878mm (34.57") of precipitation is accumulated.

Daylight

The average length of the day in September is 12h and 9min.
On the first day of September, sunrise is at 06:26 and sunset at 18:39. On the last day of the month, sunrise is at 06:21 and sunset at 18:25 -03.

Sunshine

The month with the most sunshine is September, with an average of 9.1h of sunshine.

UV index

July through November, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for the ordinary person.
Note: The UV index of 7 in September translates into these instructions:
Deter overexposure. Protecting against the sun's effects is essential. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.

Updated: Jan 31, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

The high-temperature in Flèche, French Guiana, during September is 32.7°C (90.9°F) and the low-temperature is 22.5°C (72.5°F). In September, the average heat index (a.k.a. 'felt air temperature', 'apparent temperature'), which factors the actual air temperature with the relative humidity, is appraised at 47°C (116.6°F).

The average relative humidity in September in Flèche is 79%.

In Flèche, French Guiana, in September, during 11.5 rainfall days, 26mm (1.02") of precipitation is typically accumulated.

In Flèche, the average day length in September is 12h and 9min.

In September, on the first day of the month, sunrise is at 06:26 and sunset at 18:39. On the last day of the month, in Flèche, sunrise is at 06:21 and sunset at 18:25 -03.

The month with the most sunshine in Flèche, French Guiana, is September, with an average of 9.1h of sunshine.

In Flèche, French Guiana, the average sunshine duration in September is 9.1h.

July through November, with an average maximum UV index of 7, are months with the highest UV index in Flèche.

The average daily maximum UV index in September is 7. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV radiation.

Today

Tomorrow

Long-term

Year J F M A M J J A September O N D

Aug

September

Oct

Average high temperature

32°C

32.7°C

33.1°C

Average low temperature

Average pressure

Average wind speed

Average max. wind speed

7.3km/h

8km/h

9km/h

Average wind speed gusts

Average humidity

Average rainfall

Average rainfall days

Average daylight

Average sunshine

Average sunshine days

8.7

14.6

Average UV index

Average cloud cover

Average visibility

Average temperature in September
Flèche, French Guiana

Average high temperature in September: 32.7°C

The warmest month (with the highest average high temperature) is October (33.1°C).
The month with the lowest average high temperature is February (29.1°C).

Average low temperature in September: 22.5°C

The month with the highest average low temperature is May (23.3°C).
The coldest month (with the lowest average low temperature) is July (22.2°C).

Average pressure in September
Flèche, French Guiana

Average pressure in September: 1011.6mbar

The months with the highest atmospheric pressure are June and July (1012.9mbar).
The month with the lowest atmospheric pressure is November (1009.5mbar).

Average wind speed in September
Flèche, French Guiana

Average wind speed in September: 7.7km/h

The windiest months (with the highest average wind speed) are February and March (9.5km/h).
The calmest month (with the lowest average wind speed) is July (6.4km/h).

Average humidity in September
Flèche, French Guiana

Average humidity in September: 79%

The month with the highest relative humidity is June (88%).
The month with the lowest relative humidity is October (77%).

Average rainfall in September
Flèche, French Guiana

Average rainfall in September: 26mm

The wettest month (with the highest rainfall) is May (137mm).
The driest month (with the least rainfall) is October (23mm).

Average rainfall days in September
Flèche, French Guiana

Average rainfall days in September: 11.5 days

The month with the highest number of rainy days is May (28 days).
The month with the least rainy days is September (11.5 days).

Average daylight in September /
Average sunshine in September
Flèche, French Guiana

Average daylight in September: 12h and 6min

The month with the longest days is June (Average daylight: 12h and 24min).
The month with the shortest days is December (Average daylight: 11h and 48min).

Average sunshine in September: 9h and 6min

The month with the most sunshine is September (Average sunshine: 9h and 6min).
The month with the least sunshine is February (Average sunshine: 5h and 6min).

Average sunshine days in September
Flèche, French Guiana

Average sunshine days in September: 14.6 days

The month with the most sunshine days is October (16 days).
The month with the least sunshine days is May (1.8 days).

Average UV index in September
Flèche, French Guiana

Average UV index in September: 7

The months with the highest UV index are July, August, September, October and November (UV index 7).
The months with the lowest UV index are January, February, March, April, May, June and December (UV index 6).