Climate averages 1991–2020
Cincinnati weather
in September.
A warm, moderately wet month: the 4th warmest and the driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Cincinnati: daytime highs average 25.0°C and nights cool to about 15.2°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 68 mm of rain on roughly 8 days, which makes September a moderately wet month (the driest month of the year). Daylight, from sunrise to sunset, lasts about 12 h 29 min on an average September day.
The nearest other city in this atlas is Dayton (76 km away). In September its highs average 24.4°C, 0.6°C cooler than Cincinnati, with 68 mm of rain.
Among the 498 cities listed in the United States, Cincinnati ranks joint 314th of 498 for the warmest September highs and joint 204th of 498 for the driest September (rainfall, lowest first). The mean September high of those 498 cities is 26.9°C; Cincinnati is 1.9°C cooler than that mean.
From September to October, average highs fall by 6.6°C to 18.4°C, and monthly rainfall rises from 68 mm to 75 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Cincinnati climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 3.5°C-4.8°C | -4.8°C | 83 | 10.1 | 9.810 h |
| February | 5.9°C-3.5°C | -3.5°C | 75 | 9.1 | 10.711 h |
| March | 11.2°C1.0°C | 1.0°C | 105 | 10.9 | 11.912 h |
| April | 17.7°C6.8°C | 6.8°C | 118 | 12.2 | 13.213 h |
| May | 22.4°C12.5°C | 12.5°C | 117 | 13.0 | 14.314 h |
| June | 27.0°C17.3°C | 17.3°C | 106 | 12.1 | 14.915 h |
| July | 28.9°C19.5°C | 19.5°C | 88 | 11.3 | 14.615 h |
| August | 28.5°C18.9°C | 18.9°C | 75 | 9.8 | 13.714 h |
| September, selected | 25.0°C15.2°C | 15.2°C | 68 | 7.9 | 12.512 h |
| October | 18.4°C8.9°C | 8.9°C | 75 | 8.2 | 11.211 h |
| November | 11.3°C2.8°C | 2.8°C | 84 | 8.9 | 10.110 h |
| December | 5.6°C-1.9°C | -1.9°C | 92 | 10.2 | 9.59 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Dayton in SeptemberUnited States · 76 kmHigh 24.4°C · Low 15.3°C · 68 mm rain
- Lexington in SeptemberUnited States · 127 kmHigh 25.6°C · Low 15.9°C · 89 mm rain
- Muncie in SeptemberUnited States · 140 kmHigh 23.9°C · Low 14.4°C · 67 mm rain
- Louisville in SeptemberUnited States · 145 kmHigh 26.5°C · Low 16.5°C · 77 mm rain
- Indianapolis in SeptemberUnited States · 158 kmHigh 24.6°C · Low 15.2°C · 72 mm rain
- Fishers in SeptemberUnited States · 158 kmHigh 24.4°C · Low 14.8°C · 69 mm rain
- Columbus in SeptemberUnited States · 160 kmHigh 24.3°C · Low 14.6°C · 73 mm rain
- Carmel in SeptemberUnited States · 167 kmHigh 24.2°C · Low 14.8°C · 69 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Cincinnati) is explained once on the Cincinnati year overview and on the Sources, method and limits page.