Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
The arrival of September records an average high-temperature of a still tropical 86.7°F (30.4°C), closely related to the 90°F (32.2°C) observed in August. September nights are marked by an average temperature drop to a pleasant 70.9°F (21.6°C).Heat index
The average heat index in September is appraised at a very hot 100.4°F (38°C). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.It is emphasized that the heat index's values are meant for shaded zones with mild winds. When exposed to the direct sun, the heat index may augment by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'real feel', stands as a testimony to how temperature and humidity combine to impact our sense of warmth. This effect is personal, influenced by the individual's physical activity and heat sensitivity, shaped by factors including wind, attire, and metabolic variations. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Juveniles often do not understand the need to recuperate and rehydrate. Thirst is a delayed symptom of dehydration - hence, it is vital to maintain hydration, particularly during ongoing physical activities.
Perspiration is the human body's physiological response to high temperatures and is an attempt to lower body temperature through evaporation of sweat. When relative humidity is heightened, it slows the rate of evaporation, thereby decreasing the body's ability to shed heat and creating a sensation of overheating. If the body retains more heat than it can expel, the increasing temperature can lead to heat-related conditions.
Humidity
In Mermentau, the average relative humidity in September is 78%.Rainfall
In Mermentau, during September, the rain falls for 14.9 days and regularly aggregates up to 1.77" (45mm) of precipitation. Throughout the year, there are 156.6 rainfall days, and 26.34" (669mm) of precipitation is accumulated.Snowfall
February through December are months without snowfall in Mermentau.Daylight
In September, the average length of the day is 12h and 20min.On the first day of the month, sunrise is at 6:47 am and sunset at 7:32 pm. On the last day of September, sunrise is at 7:03 am and sunset at 6:56 pm CDT.
Sunshine
In September, the average sunshine is 9.9h.UV index
The average daily maximum UV index in September is 6. A UV Index value of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: The maximum UV index of 6 during September leads to these instructions:
Use measures and accept sun safety conventions. Guarding against skin and eye trauma is of high priority. Avoid direct Sun exposure and seek shade from 10 a.m. to 4 p.m., the period of highest UV radiation. Remember, however, that not all shade structures offer full protection. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
How many hours of daylight does Mermentau have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Mermentau have in September?
How high is the UV index in September?
Average temperature in September
Mermentau, LA
- Average high temperature in September: 86.7°F
The warmest month (with the highest average high temperature) is August (90°F).
The month with the lowest average high temperature is January (59°F).
- Average low temperature in September: 70.9°F
The months with the highest average low temperature are July and August (75.2°F).
The coldest month (with the lowest average low temperature) is January (44.2°F).
Average pressure in September
Mermentau, LA
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Mermentau, LA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is February (9.2mph).
The calmest month (with the lowest average wind speed) is August (5.8mph).
Average humidity in September
Mermentau, LA
- Average humidity in September: 78%
The month with the highest relative humidity is February (81%).
The month with the lowest relative humidity is October (72%).
Average rainfall in September
Mermentau, LA
- Average rainfall in September: 1.77"
The wettest month (with the highest rainfall) is August (3.58").
The driest month (with the least rainfall) is February (1.61").
Average rainfall days in September
Mermentau, LA
- Average rainfall days in September: 14.9 days
The month with the highest number of rainy days is August (18.6 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in September
Mermentau, LA
- Average snowfall in September: 0"
The month with the highest snowfall is January (0.12").
The months with the least snowfall are February, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Mermentau, LA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.3 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
Mermentau, LA
- Average daylight in September: 12h and 2min
The month with the longest days is June (Average daylight: 14h and 6min).
The month with the shortest days is December (Average daylight: 10h and 12min).
- Average sunshine in September: 9h and 5min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days in September
Mermentau, LA
- Average sunshine days in September: 12.5 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is August (9.9 days).
Average UV index in September
Mermentau, 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
Mermentau, LA
- Average cloud cover in September: 28
The month with the most cloud cover is February (Cloud cover 47).
The month with the least cloud cover is October (Cloud cover 25).
Average visibility in September
Mermentau, 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).
Mermentau, Louisiana, USA
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