Climate averages 1991–2020
Frankfurt am Main weather
in September.
A mild, moderately wet month: the 4th warmest and the 3rd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Frankfurt am Main: daytime highs average 19.9°C and nights cool to about 11.3°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 52 mm of rain on roughly 9 days, which makes September a moderately wet month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 41 min on an average September day.
The nearest other city in this atlas is Offenbach (6 km away). In September its highs average 19.9°C, about as warm as Frankfurt am Main, with 52 mm of rain.
Among the 120 cities listed in Germany, Frankfurt am Main ranks joint 9th of 120 for the warmest September highs and joint 6th of 120 for the driest September (rainfall, lowest first). The mean September high of those 120 cities is 18.8°C; Frankfurt am Main is 1.1°C warmer than that mean.
From September to October, average highs fall by 5.6°C to 14.3°C, and monthly rainfall rises from 52 mm to 54 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
Frankfurt am Main climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 4.4°C-0.6°C | -0.6°C | 56 | 11.7 | 8.69 h |
| February | 6.0°C-0.5°C | -0.5°C | 49 | 10.1 | 10.010 h |
| March | 10.2°C1.9°C | 1.9°C | 54 | 11.3 | 11.812 h |
| April | 14.9°C5.0°C | 5.0°C | 44 | 9.6 | 13.714 h |
| May | 18.7°C9.4°C | 9.4°C | 63 | 10.5 | 15.415 h |
| June | 22.2°C12.9°C | 12.9°C | 55 | 9.9 | 16.316 h |
| July | 24.4°C15.1°C | 15.1°C | 60 | 10.8 | 15.916 h |
| August | 24.4°C15.0°C | 15.0°C | 53 | 9.2 | 14.514 h |
| September, selected | 19.9°C11.3°C | 11.3°C | 52 | 8.5 | 12.713 h |
| October | 14.3°C7.3°C | 7.3°C | 54 | 10.5 | 10.811 h |
| November | 8.6°C3.3°C | 3.3°C | 58 | 11.1 | 9.19 h |
| December | 5.0°C0.4°C | 0.4°C | 68 | 13.9 | 8.28 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
- Offenbach in SeptemberGermany · 6 kmHigh 19.9°C · Low 11.3°C · 52 mm rain
- Hanau am Main in SeptemberGermany · 17 kmHigh 19.8°C · Low 11.3°C · 58 mm rain
- Darmstadt in SeptemberGermany · 27 kmHigh 19.8°C · Low 11.4°C · 61 mm rain
- Wiesbaden in SeptemberGermany · 32 kmHigh 19.8°C · Low 11.8°C · 54 mm rain
- Mainz in SeptemberGermany · 32 kmHigh 20.0°C · Low 11.4°C · 54 mm rain
- Gießen in SeptemberGermany · 52 kmHigh 18.9°C · Low 10.8°C · 55 mm rain
- Worms in SeptemberGermany · 59 kmHigh 20.2°C · Low 11.5°C · 51 mm rain
- Mannheim in SeptemberGermany · 71 kmHigh 20.4°C · Low 11.8°C · 55 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 Frankfurt am Main) is explained once on the Frankfurt am Main year overview and on the Sources, method and limits page.
Offenbach lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.