September weather forecastAtlanta, GA
September
Weather in September
September brings about a semblance of relief from summer's intense heat, marking the arrival of early autumn. In light of the drop in temperature from August, highs reach 84.2°F (29°C), offering more cooling relief. Gradual changes in the environment begin to unearth, with shorter days and falling leaves. Rainfall is significantly lower compared to previous months, offering an uninterrupted September experience. Despite the early signs of autumn, plantation around the city remains radiant under plenty of sunshine.Temperature
September's arrival in Atlanta registers an average high-temperature of a moderately hot 84.2°F (29°C), closely aligning with the temperature of the previous month. Atlanta's nights in September cool down to an average low-temperature of 65.5°F (18.6°C).Heat index
For September, the heat index is estimated at a hot 91.4°F (33°C). Ensure heightened precautions, risk of heat cramps and heat exhaustion is significant. Sustained activity could provoke heatstroke.Data suggests that the heat index is set for environments in shade and with a light wind. An exposure to direct sunlight may lift the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', comes about by integrating the temperature readings with the humidity levels. Depending on the activity and the individual's heat perception, which may vary due to factors including wind, clothing, and metabolic variations, this effect remains subjective. Given the impact of direct sunlight, it's noteworthy that the felt temperature can rise by 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. In general, children are more at risk than adults because they sweat less. Furthermore, the large skin surface compared to their small bodies and the high heat production due to their actions contribute to this vulnerability.
Humidity
In September, the average relative humidity in Atlanta is 70%.Rainfall
September is the month with the least rainfall. Rain falls for 8.6 days and accumulates 0.55" (14mm) of precipitation.Snowfall
April through November are months without snowfall.Daylight
The average length of the day in September in Atlanta, Georgia, is 12h and 22min.On the first day of the month, sunrise is at 7:11 am and sunset at 8:02 pm. On the last day of September, sunrise is at 7:31 am and sunset at 7:22 pm EDT.
Sunshine
In Atlanta, the average sunshine in September is 8.7h.UV index
In Atlanta, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: In September, the average maximum UV index of 5 translates into the following recommendations:
Act with care - The need to guard against sun damage is communicated. Being exposed to the midday Sun can have harmful effects due to strong UV radiation; always take precautions. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Atlanta, GA
- Average high temperature in September: 84.2°F
The warmest month (with the highest average high temperature) is July (90.7°F).
The month with the lowest average high temperature is January (50.5°F).
- Average low temperature in September: 65.5°F
The month with the highest average low temperature is July (71.6°F).
The coldest month (with the lowest average low temperature) is January (34.9°F).
Average pressure in September
Atlanta, GA
- Average pressure in September: 30.03"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.99"Hg).
Average wind speed in September
Atlanta, GA
- Average wind speed in September: 4.8mph
The windiest month (with the highest average wind speed) is January (8mph).
The calmest month (with the lowest average wind speed) is August (4.5mph).
Average humidity in September
Atlanta, GA
- Average humidity in September: 70%
The month with the highest relative humidity is December (77%).
The months with the lowest relative humidity are July and August (69%).
Average rainfall in September
Atlanta, GA
- Average rainfall in September: 0.55"
The wettest month (with the highest rainfall) is August (2.32").
The driest month (with the least rainfall) is September (0.55").
Average rainfall days in September
Atlanta, GA
- Average rainfall days in September: 8.6 days
The month with the highest number of rainy days is August (17.1 days).
The month with the least rainy days is November (6.9 days).
Average snowfall in September
Atlanta, GA
- Average snowfall in September: 0"
The month with the highest snowfall is February (0.2").
The months with the least snowfall are April, May, June, July, August, September, October and November (0").
Average snowfall days in September
Atlanta, GA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (0.9 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Atlanta, GA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in September: 8h and 42min
The months with the most sunshine are June and July (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days in September
Atlanta, GA
- Average sunshine days in September: 19.2 days
The month with the most sunshine days is October (22.6 days).
The month with the least sunshine days is July (10.9 days).
Average UV index in September
Atlanta, GA
- Average UV index in September: 5
The month with the highest UV index is August (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in September
Atlanta, GA
- Average cloud cover in September: 30
The month with the most cloud cover is December (Cloud cover 46).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility in September
Atlanta, 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).
