September weather forecastGrandbois, LA
September
Weather in September
September, the first month of the autumn in Grandbois, is still a hot month, with temperature in the range of an average low of 73.6°F (23.1°C) and an average high of 86.7°F (30.4°C).Temperature
With September's arrival, Grandbois's weather records an average high-temperature of a still tropical 86.7°F (30.4°C), marking little difference from August's 89.1°F (31.7°C). During the month of September, an average temperature of 73.6°F (23.1°C) is noted during the nights.Heat index
September's mean heat index is calculated to be a torrid 100.4°F (38°C). Exercise enhanced safety steps, heat cramps and heat exhaustion are probable. Heatstroke could be a result of sustained activity.The heat index's values are generally associated with conditions in shade and light breezes. The heat index could see an increase by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is an index that combines air temperature and relative humidity to determine the human-perceived temperature equivalent. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. Considering the impact of direct sunlight, it's possible for the heat index to surge by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Typically, young kids are at a higher risk than adults since they sweat less. Also, the larger skin surface in proportion to their small bodies and the heightened heat production due to their active nature adds to their vulnerability.
Evaporating sweat, thanks to perspiration, acts as a natural air conditioner for the human body. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. Heat-related disorders may develop if heat gain in the body overshadows its cooling capacity, leading to elevated temperatures.
Humidity
The average relative humidity in September is 77%.Rainfall
In September, the rain falls for 16 days. Throughout September, 1.42" (36mm) of precipitation is accumulated. Throughout the year, there are 145.4 rainfall days, and 19.13" (486mm) of precipitation is accumulated.Snowfall
February through December are months without snowfall.Daylight
In Grandbois, the average length of the day in September is 12h and 20min.On the first day of the month, sunrise is at 6:39 am and sunset at 7:23 pm. On the last day of September, in Grandbois, sunrise is at 6:55 am and sunset at 6:48 pm CDT.
Sunshine
In September, the average sunshine is 10.1h.UV index
In Grandbois, Louisiana, the average daily maximum UV index in September is 6. A UV Index of 6 to 7 symbolizes a high threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum UV index of 6 in September translates into the following recommendations:
Prevent overexposure. Protection from the sun's harmful effects is needed. Avoid direct Sun exposure and seek shade between 10 a.m. and 4 p.m., when UV radiation is at its peak, but keep in mind that not all shade structures provide complete protection. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Grandbois, LA
- Average high temperature in September: 86.7°F
The warmest month (with the highest average high temperature) is July (89.2°F).
The month with the lowest average high temperature is January (61.3°F).
- Average low temperature in September: 73.6°F
The month with the highest average low temperature is August (77°F).
The coldest month (with the lowest average low temperature) is January (47.1°F).
Average pressure in September
Grandbois, LA
- Average pressure in September: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.97"Hg).
Average wind speed in September
Grandbois, LA
- Average wind speed in September: 6mph
The windiest months (with the highest average wind speed) are February and April (8.8mph).
The calmest months (with the lowest average wind speed) are July and August (5.5mph).
Average humidity in September
Grandbois, LA
- Average humidity in September: 77%
The month with the highest relative humidity is December (78%).
The month with the lowest relative humidity is October (73%).
Average rainfall in September
Grandbois, LA
- Average rainfall in September: 1.42"
The wettest month (with the highest rainfall) is August (3.39").
The driest month (with the least rainfall) is March (0.75").
Average rainfall days in September
Grandbois, LA
- Average rainfall days in September: 16 days
The month with the highest number of rainy days is July (20.5 days).
The month with the least rainy days is November (6.4 days).
Average snowfall days in September
Grandbois, LA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.2 days).
The months with the least snowfall days are February, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in September /
Average sunshine in September
Grandbois, LA
- Average daylight in September: 12h and 18min
The month with the longest days is June (Average daylight: 14h and 0min).
The month with the shortest days is December (Average daylight: 10h and 18min).
- Average sunshine in September: 10h and 6min
The month with the most sunshine is June (Average sunshine: 10h and 48min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).
Average sunshine days in September
Grandbois, LA
- Average sunshine days in September: 10.8 days
The month with the most sunshine days is November (21.8 days).
The month with the least sunshine days is July (6.8 days).
Average UV index in September
Grandbois, LA
- Average UV index in September: 6
The months with the highest UV index are May, June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Grandbois, LA
- Average cloud cover in September: 26
The month with the most cloud cover is December (Cloud cover 44).
The month with the least cloud cover is October (Cloud cover 24).
Average visibility in September
Grandbois, LA
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





