September weather forecastSaint Simons Island, GA
September
Weather in September
September brings a slow transition from the hot summer temperatures to a more comfortable fall climate on Saint Simons Island. It places a halt on the sequence of increasing rainfall from the summer, causing a reverse. The visible shortening of days and more moderate heat levels differ drastically from the conditions experienced in August. The main highlight of September is its reduced average rainfall of 2.8" (71mm), a significant decrease from August's high. It also signifies the nearing end of the main tourist season, offering a more relaxed atmosphere for visitors who linger.Temperature
The shift into September uncovers an average high-temperature of a moderately hot 84.9°F (29.4°C), subtly different from the previous month. Throughout September, the average low-temperature records at 74.3°F (23.5°C).Heat index
September's heat index is calculated to be a torrid 95°F (35°C). Ensure heightened precautions, risk of heat cramps and heat exhaustion is significant. Sustained activity could provoke heatstroke.Metrics for the heat index primarily focus on shaded spots and light wind conditions. When exposed to the direct sun, the heat index may augment by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. Elements of metabolic variation, physical activity, and clothing contribute to the effect of temperature on an individual. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Youngsters often neglect the necessity for rest and hydration. Thirst is a sign of advancing dehydration - thus the importance of maintaining hydration, specifically during long-lasting physical activities.
For the human body, perspiration is the go-to method to regulate temperature, using sweat's evaporation to dissipate warmth. An upsurge in relative humidity affects normal body cooling mechanisms by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. Overheating dangers loom when the body's heat release mechanisms are overshadowed by excessive gain.
Humidity
The average relative humidity in September in Saint Simons Island is 77%.Rainfall
In September, the rain falls for 19.2 days. Throughout September, 2.8" (71mm) of precipitation is accumulated. Throughout the year, there are 163.3 rainfall days, and 20.43" (519mm) of precipitation is accumulated.Snowfall
In Saint Simons Island, snow does not fall in January, March through November.Ocean temperature
In Saint Simons Island, in September, the average water temperature is 82.4°F (28°C).Note: Water temperature ranging from 77°F (25°C) to 84.2°F (29°C) is recognized as warm and pleasant by all, making water activities comfortable and delightful for long durations.
Daylight
In Saint Simons Island, Georgia, the average length of the day in September is 12h and 20min.On the first day of September, sunrise is at 7:02 am and sunset at 7:48 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 7:11 pm EDT.
Sunshine
In Saint Simons Island, the average sunshine in September is 8.6h.UV index
The months with the highest UV index are May through September, with an average maximum UV index of 7. A UV Index value of 6 to 7 symbolizes a high health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: The daily high UV index of 7 in September translates into this advice:
Undertake precautions and comply with sun safety standards. Protection from skin and eye injury is vital. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes. Warning! Sand and water reflections boost the intensity of UV exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Saint Simons Island, GA
- Average high temperature in September: 84.9°F
The warmest month (with the highest average high temperature) is July (88.7°F).
The month with the lowest average high temperature is January (60.4°F).
- Average low temperature in September: 74.3°F
The month with the highest average low temperature is August (77.4°F).
The coldest month (with the lowest average low temperature) is January (47.7°F).
Average pressure in September
Saint Simons Island, GA
- Average pressure in September: 29.98"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.98"Hg).
Average wind speed in September
Saint Simons Island, GA
- Average wind speed in September: 7.6mph
The windiest months (with the highest average wind speed) are January and April (8.8mph).
The calmest month (with the lowest average wind speed) is August (6.9mph).
Average humidity in September
Saint Simons Island, GA
- Average humidity in September: 77%
The months with the highest relative humidity are August and December (78%).
The month with the lowest relative humidity is March (72%).
Average rainfall in September
Saint Simons Island, GA
- Average rainfall in September: 2.8"
The wettest month (with the highest rainfall) is August (3.43").
The driest month (with the least rainfall) is January (0.59").
Average rainfall days in September
Saint Simons Island, GA
- Average rainfall days in September: 19.2 days
The month with the highest number of rainy days is August (23.3 days).
The month with the least rainy days is January (8.2 days).
Average snowfall days in September
Saint Simons Island, GA
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are February and December (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October and November (0 days).
Average sea temperature in September
Saint Simons Island, GA
- Average sea temperature in September: 82.4°F
The best month for swimming (with the highest average sea temperature) is August (83.4°F).
The coldest month (with the lowest average sea temperature) is February (58.5°F).
Average daylight in September /
Average sunshine in September
Saint Simons Island, GA
- Average daylight in September: 12h and 18min
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: 8h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in September
Saint Simons Island, GA
- Average sunshine days in September: 7.4 days
The month with the most sunshine days is March (20.1 days).
The month with the least sunshine days is August (4.2 days).
Average UV index in September
Saint Simons Island, GA
- 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 January (UV index 3).
Average cloud cover in September
Saint Simons Island, GA
- Average cloud cover in September: 30
The months with the most cloud cover are February and December (Cloud cover 38).
The months with the least cloud cover are April, May, June and July (Cloud cover 27).
Average visibility in September
Saint Simons Island, GA
- 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).
