September weather forecastMetairie, LA
September
Weather in September
In September, Metairie begins its transition from the scorching summer towards a milder autumn. The temperature, after prolonged summer heat, takes a dive returning to the more desirable 80s°F. Rainfall and humidity begin to level off, yet they continue to influence the weather significantly. The shift towards autumn heralds a reduction in the duration of daylight hours, signaling shorter days ahead. Despite this transition, the frequency of sunshine continues on its summer trend, with an average of 10.2 hours per day.Temperature
Metairie's September showcases an average high-temperature of a still hot 86.5°F (30.3°C), hardly distinct from August's 89.1°F (31.7°C). An average minimum temperature of 75.2°F (24°C) is recorded during the month of September.Heat index
The average heat index in September is calculated to be a very hot 98.6°F (37°C). Extra safeguards are necessary to prevent heat exhaustion and heat cramps. Prolonged activity might cause heatstroke.It is noted that heat index values are ascertained for locations in the shade and with gentle breezes. The direct sunshine could escalate the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'feels like', is a single figure representing how weather conditions feel when combining temperature and humidity. One's perception of weather can be shaped by other factors, involving metabolic differences, pregnancy, and physical exertion. Under direct sun rays, the felt temperature might be heightened, with the heat index increasing by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for babies and toddlers. Young ones often disregard the necessity to rest and hydrate. Thirst usually indicates advanced dehydration - hence, it is key to stay hydrated, particularly during ongoing physical activities.
One of the main methods the human body employs to cool down is by perspiring, as this process allows sweat to evaporate and remove excess heat. During conditions of high air temperature and humidity (high heat index), the body's ability to perspire is inhibited, increasing the sensation of warmth. The body is at risk of dehydration and related complications when it fails to shed excessive heat.
Humidity
In September, the average relative humidity is 74%.Rainfall
In Metairie, in September, it is raining for 10.9 days, with typically 0.43" (11mm) of accumulated precipitation. Throughout the year, there are 104.1 rainfall days, and 8.39" (213mm) of precipitation is accumulated.Daylight
The average length of the day in September is 12h and 20min.On the first day of the month, sunrise is at 6:38 am and sunset at 7:22 pm. On the last day of September, sunrise is at 6:53 am and sunset at 6:46 pm CDT.
Sunshine
In Metairie, the average sunshine in September is 10.2h.UV index
May through September, with an average maximum UV index of 7, are months with the highest UV index. A UV Index of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for average individuals.Note: A daily maximum UV index of 7 in September translates into the following instructions:
Undertake protective measures and comply with sun safety rules. Shielding against skin and eye damage is essential. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Metairie, LA
- Average high temperature in September: 86.5°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 (60.4°F).
- Average low temperature in September: 75.2°F
The month with the highest average low temperature is August (79°F).
The coldest month (with the lowest average low temperature) is January (47.8°F).
Average pressure in September
Metairie, 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
Metairie, LA
- Average wind speed in September: 6.9mph
The windiest months (with the highest average wind speed) are February and April (9.5mph).
The calmest months (with the lowest average wind speed) are July and August (6.5mph).
Average humidity in September
Metairie, LA
- Average humidity in September: 74%
The month with the highest relative humidity is December (78%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Metairie, LA
- Average rainfall in September: 0.43"
The wettest month (with the highest rainfall) is July (1.3").
The driest month (with the least rainfall) is March (0.39").
Average rainfall days in September
Metairie, LA
- Average rainfall days in September: 10.9 days
The month with the highest number of rainy days is August (14.8 days).
The month with the least rainy days is November (4.5 days).
Average daylight in September /
Average sunshine in September
Metairie, 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 12min
The month with the most sunshine is June (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days in September
Metairie, LA
- Average sunshine days in September: 14.8 days
The month with the most sunshine days is November (24.6 days).
The month with the least sunshine days is August (10.3 days).
Average UV index in September
Metairie, LA
- Average UV index in September: 7
The months with the highest UV index are May, June, July, August and September (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in September
Metairie, LA
- Average cloud cover in September: 25
The month with the most cloud cover is December (Cloud cover 45).
The month with the least cloud cover is October (Cloud cover 24).
Average visibility in September
Metairie, 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).





