September weather forecastCincinnati, OH

September
Weather in September
The onset of September in Cincinnati marks a clear transition from summer's warmth to autumn's much cooler embrace. Welcoming the change, the city's leafy landscapes dress in a riot of colors, making the environment visually stunning and unique. Temperatures begin to mellow, with the highs dipping to a less sultry 77.9°F (25.5°C), the significant drop signifying the departure from the balmy summer temperatures. This month hosts a farewell to the hot and vibrant summer, welcoming the crisp and colorful fall.Temperature
September's arrival aligns with a minor decrease in average high-temperatures, from August's 83.8°F (28.8°C) to a still moderately hot 77.9°F (25.5°C). During the nights in September, Cincinnati experiences a consistent average temperature of 58.6°F (14.8°C).Humidity
The months with the lowest humidity are August through October, with an average relative humidity of 74%.Rainfall
September is the month with the least rainfall. Rain falls for 12.1 days and accumulates 1.54" (39mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 7:07 am and sunset at 8:08 pm. On the last day of the month, sunrise is at 7:33 am and sunset at 7:21 pm EDT.
Sunshine
The average sunshine in September in Cincinnati is 8.3h.UV index
In Cincinnati, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: In September, a daily UV index of 4 turns into the following recommendations:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Cincinnati, OH
- Average high temperature in September: 77.9°F
The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (36.1°F).
- Average low temperature in September: 58.6°F
The month with the highest average low temperature is July (66°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).
Average pressure in September
Cincinnati, OH
- Average pressure in September: 30.03"Hg
The months with the highest atmospheric pressure are January and November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Cincinnati, OH
- Average wind speed in September: 5.7mph
The windiest month (with the highest average wind speed) is January (8.7mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in September
Cincinnati, OH
- Average humidity in September: 74%
The months with the highest relative humidity are February and December (81%).
The months with the lowest relative humidity are August, September and October (74%).
Average rainfall in September
Cincinnati, OH
- Average rainfall in September: 1.54"
The wettest month (with the highest rainfall) is May (3.27").
The driest month (with the least rainfall) is September (1.54").
Average rainfall days in September
Cincinnati, OH
- Average rainfall days in September: 12.1 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is February (8.2 days).
Average snowfall in September
Cincinnati, OH
- Average snowfall in September: 0"
The month with the highest snowfall is February (2.01").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Cincinnati, OH
- Average snowfall days in September: 0 days
The months with the highest number of snowfall days are January and February (5.5 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Cincinnati, OH
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 8h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in September
Cincinnati, OH
- Average sunshine days in September: 16.2 days
The months with the most sunshine days are October and November (19.2 days).
The month with the least sunshine days is May (10.9 days).
Average UV index in September
Cincinnati, OH
- Average UV index in September: 4
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Cincinnati, OH
- Average cloud cover in September: 33
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Cincinnati, OH
- 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).





