September weather forecastStart, LA
September
Weather in September
September, the first month of the autumn in Start, is still a hot month, with an average temperature ranging between min 68.2°F (20.1°C) and max 87.1°F (30.6°C).Temperature
In September, Start experiences a minor shift in meteorological conditions with average high-temperatures marked at a still tropical 87.1°F (30.6°C), closely mirroring the climate in August. An average low-temperature of 68.2°F (20.1°C) is recorded in the month of September.Heat index
Throughout September, the heat index is computed to be a fiery hot 98.6°F (37°C). Extra precautions are necessary, heat cramps and heat exhaustion are plausible outcomes. Extended activity could lead to heatstroke.Be informed that the heat index values are oriented around shady conditions and gentle breezes. The heat index may experience an enhancement of 15 Fahrenheit (8 Celsius) degrees under direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'feels like', provides an understanding of perceived warmth by combining temperature and relative humidity. The impact of temperature is individual, as people's perception of weather may change based on their body mass, height, and physical activity. Direct sunlight exposure should be noted as it has the potential to increase the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly meaningful for babies and toddlers. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
The human body normally cools itself by perspiration. Excessive warmth is eliminated from the body by evaporation of sweat. Under high air temperature and high humidity (high heat index) conditions, the body's ability to perspire is compromised, increasing the sensation of heat. When heat uptake goes beyond the body's cooling mechanisms, there's a surge in body temperature, posing health risks.
Humidity
The average relative humidity in September is 72%.Rainfall
September is the month with the least rainfall in Start. Rain falls for 12.1 days and accumulates 1.69" (43mm) of precipitation.Snowfall
April through December are months without snowfall.Daylight
The average length of the day in September is 12h and 22min.On the first day of the month, sunrise is at 6:42 am and sunset at 7:31 pm. On the last day of September, sunrise is at 7:01 am and sunset at 6:53 pm CDT.
Sunshine
In September, the average sunshine is 9.8h.UV index
The average daily maximum UV index in September is 6. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for the average person.Note: In September, an average UV index of 6 transforms into the following instructions:
Inhibit overexposure. Warding off sun damage is of utmost importance. Try to minimize direct Sun exposure between 10 a.m. and 4 p.m., the peak period for UV radiation. Also note that objects like parasols or canopies might not provide complete sun protection. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Start, LA
- Average high temperature in September: 87.1°F
The warmest month (with the highest average high temperature) is July (91.8°F).
The month with the lowest average high temperature is January (53.6°F).
- Average low temperature in September: 68.2°F
The month with the highest average low temperature is July (73.6°F).
The coldest month (with the lowest average low temperature) is January (39.6°F).
Average pressure in September
Start, LA
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Start, LA
- Average wind speed in September: 5.5mph
The windiest month (with the highest average wind speed) is February (8.5mph).
The calmest months (with the lowest average wind speed) are August and September (5.5mph).
Average humidity in September
Start, LA
- Average humidity in September: 72%
The month with the highest relative humidity is February (81%).
The month with the lowest relative humidity is October (68%).
Average rainfall in September
Start, LA
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is April (4.06").
The driest month (with the least rainfall) is September (1.69").
Average rainfall days in September
Start, LA
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is July (15.6 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in September
Start, LA
- Average snowfall in September: 0"
The months with the highest snowfall are January and February (0.16").
The months with the least snowfall are April, May, June, July, August, September, October, November and December (0").
Average snowfall days in September
Start, LA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.7 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).
Average daylight in September /
Average sunshine in September
Start, LA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 6min).
- Average sunshine in September: 9h and 48min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Start, LA
- Average sunshine days in September: 15.3 days
The month with the most sunshine days is October (20.2 days).
The month with the least sunshine days is July (12.8 days).
Average UV index in September
Start, LA
- Average UV index in September: 6
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January and December (UV index 3).
Average cloud cover in September
Start, LA
- Average cloud cover in September: 28
The month with the most cloud cover is February (Cloud cover 49).
The months with the least cloud cover are June and October (Cloud cover 27).
Average visibility in September
Start, 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).





