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 days in September
- Average sea temperature 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
Grand Isle's September showcases an average high-temperature of a moderately hot 84.6°F (29.2°C), hardly distinct from August's 86.9°F (30.5°C). Grand Isle's nocturnal September readings average at 78.8°F (26°C), showing little variation from the daytime temperatures.Heat index
The heat index value for September is appraised at a tropical 93.2°F (34°C). Take more safety measures, heat exhaustion and heat cramps are potential outcomes. Persistent activity might lead to heatstroke.Records show heat index calculations are tailored for shaded regions and mild winds. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'feels like', takes into account both air temperature and humidity to illustrate what people actually feel. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. Exposure to direct sun rays can influence the heat you feel, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Young individuals are generally in more danger than adults due to their lower capacity to sweat. Moreover, their large skin surface in relation to their small bodies and the increased heat generation from their activities makes them more vulnerable.
Humidity
The average relative humidity in September in Grand Isle is 73%.Rainfall
In September, in Grand Isle, the rain falls for 17.3 days. Throughout September, 2.17" (55mm) of precipitation is accumulated. Throughout the year, there are 151.9 rainfall days, and 22.01" (559mm) of precipitation is accumulated.Snowfall
February through December are months without snowfall in Grand Isle.Ocean temperature
In September, the average ocean temperature is 83.8°F (28.8°C).Note: Temperatures between 77°F (25°C) and 84.2°F (29°C) are excellent for swimming, diving, and other water activities, providing comfort and enjoyment for extended periods without discomfort.
Daylight
In September, the average length of the day in Grand Isle, Louisiana, is 12h and 20min.On the first day of September, sunrise is at 6:37 am and sunset at 7:21 pm. On the last day of the month, sunrise is at 6:52 am and sunset at 6:46 pm CDT.
Sunshine
In Grand Isle, Louisiana, 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 in Grand Isle. A UV Index value of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for average individuals.Note: The maximum daily UV index of 7 during September translates into the following directions:
Deter overexposure. Protecting against the sun's effects is essential. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears. Attention! UV strength is notably upped by the reflection of sand and water.
Frequently asked questions
How hot does it get in Grand Isle in September?
What is the average humidity in September in Grand Isle?
How many days does it rain in September in Grand Isle?
When it does not snow in Grand Isle?
What is the water temperature in September in Grand Isle?
What is the average length of the day in September in Grand Isle?
When are sunrise and sunset in September in Grand Isle?
How many hours of sunshine does Grand Isle have in September?
When is the highest UV index in Grand Isle?
What is the UV index intensity in September in Grand Isle?
Average temperature in September
Grand Isle, LA
- Average high temperature in September: 84.6°F
The warmest months (with the highest average high temperature) are July and August (86.9°F).
The month with the lowest average high temperature is January (61.7°F).
- Average low temperature in September: 78.8°F
The month with the highest average low temperature is August (81.3°F).
The coldest month (with the lowest average low temperature) is January (53.1°F).
Average pressure in September
Grand Isle, LA
- Average pressure in September: 29.96"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is September (29.96"Hg).
Average wind speed in September
Grand Isle, LA
- Average wind speed in September: 8.8mph
The windiest month (with the highest average wind speed) is January (12.4mph).
The calmest month (with the lowest average wind speed) is July (8mph).
Average humidity in September
Grand Isle, LA
- Average humidity in September: 73%
The months with the highest relative humidity are February and December (78%).
The month with the lowest relative humidity is October (71%).
Average rainfall in September
Grand Isle, LA
- Average rainfall in September: 2.17"
The wettest month (with the highest rainfall) is August (4.72").
The driest months (with the least rainfall) are February and April (0.87").
Average rainfall days in September
Grand Isle, LA
- Average rainfall days in September: 17.3 days
The month with the highest number of rainy days is August (20.7 days).
The month with the least rainy days is November (7.5 days).
Average snowfall days in September
Grand Isle, LA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (0.1 days).
The months with the least snowfall days are February, March, April, May, June, July, August, September, October, November and December (0 days).
Average sea temperature in September
Grand Isle, LA
- Average sea temperature in September: 83.8°F
The best month for swimming (with the highest average sea temperature) is August (87.5°F).
The coldest month (with the lowest average sea temperature) is January (61.4°F).
Average daylight in September /
Average sunshine in September
Grand Isle, LA
- Average daylight in September: 12h and 2min
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 1min
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 24min).
Average sunshine days in September
Grand Isle, LA
- Average sunshine days in September: 8.6 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is August (6.5 days).
Average UV index in September
Grand Isle, 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 months with the lowest UV index are January and December (UV index 4).
Average cloud cover in September
Grand Isle, LA
- Average cloud cover in September: 25
The month with the most cloud cover is December (Cloud cover 42).
The month with the least cloud cover is May (Cloud cover 23).
Average visibility in September
Grand Isle, 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).
Grand Isle, Louisiana, USA
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