September weather forecast
Eau Claire, French Guiana

The first month of the autumn, September, is also a hot month in Eau Claire, French Guiana, with an average temperature fluctuating between 20.5°C (68.9°F) and 34.1°C (93.4°F).

Temperature

The beginning of September records an average high-temperature of a still tropical 34.1°C (93.4°F), almost echoing the conditions of the previous month. September nights bring a pronounced temperature shift, with averages hovering around an agreeable 20.5°C (68.9°F).

Heat index

The heat index value for September is calculated to be a blazing hot 49°C (120.2°F). Notice: Heat cramps and heat exhaustion are likely. Continued strenuous activity might lead to heatstroke.
The heat index's values are generally associated with conditions in shade and light breezes. 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 'real feel' or 'apparent temperature', binds temperature metrics with humidity values to give a sense of the actual warmth. The individual's impression of temperature can be shaped by additional aspects such as metabolic variations, physical activity, and clothing. Consider that direct sun exposure can intensify the felt heat, adding potentially 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are particularly important for children. Young people are generally more susceptible than adults because they perspire less. Furthermore, their proportionally larger skin surface to their petite bodies and the increased heat output from their actions add to the risk.
Perspiring is how the human body naturally cools down, as sweat's evaporation takes away excess heat. In situations of high air temperature combined with high humidity (significant heat index), the body's ability to perspire is reduced, heightening the sense of warmth. Overheating can ensue when the body accumulates more heat than it can release, and dehydration severity may vary.

Humidity

In September, the average relative humidity in Eau Claire is 74%.

Rainfall

In September, the rain falls for 14.3 days. Throughout September, 36mm (1.42") of precipitation is accumulated. In Eau Claire, during the entire year, the rain falls for 265.5 days and collects up to 1078mm (42.44") of precipitation.

Daylight

In Eau Claire, the average length of the day in September is 12h and 8min.
On the first day of September, sunrise is at 06:28 and sunset at 18:39. On the last day of the month, sunrise is at 06:21 and sunset at 18:26 -03.

Sunshine

September and October, with an average of 8.8h of sunshine, are months with the most sunshine in Eau Claire.

UV index

The months with the highest UV index are August 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 ordinary person.
Note: A daily high UV index of 7 in September leads to these guidelines:
Stick with precautions and abide by sun safety procedures. Evading sunburn is essential. It's important to stay in the shade and limit exposure to the sun from 10 a.m. to 4 p.m., when UV radiation is most intense, although remember that shade structures may not provide full sun protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat.