Climate averages 1991–2020
Zürich weather
in September.
A mild, wet month: the 4th warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Zürich: daytime highs average 18.9°C and nights cool to about 11.2°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 123 mm of rain on roughly 12 days, which makes September a wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 37 min on an average September day.
The nearest other city in this atlas is Winterthur (20 km away). In September its highs average 18.7°C, about as warm as Zürich, with 91 mm of rain.
Among the 8 cities listed in Switzerland, Zürich ranks joint 3rd of 8 for the warmest September highs and 6th of 8 for the driest September (rainfall, lowest first). The mean September high of those 8 cities is 18.8°C; Zürich is 0.1°C warmer than that mean.
From September to October, average highs fall by 4.3°C to 14.6°C, and monthly rainfall falls from 123 mm to 103 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
Zürich climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 4.8°C-1.4°C | -1.4°C | 92 | 12.9 | 8.99 h |
| February | 6.1°C-1.5°C | -1.5°C | 85 | 11.9 | 10.210 h |
| March | 10.3°C1.1°C | 1.1°C | 98 | 14.2 | 11.912 h |
| April | 14.1°C4.2°C | 4.2°C | 106 | 13.9 | 13.614 h |
| May | 17.9°C8.6°C | 8.6°C | 144 | 16.0 | 15.115 h |
| June | 21.4°C12.5°C | 12.5°C | 143 | 15.5 | 15.916 h |
| July | 23.3°C14.6°C | 14.6°C | 146 | 15.4 | 15.516 h |
| August | 23.2°C15.0°C | 15.0°C | 147 | 14.4 | 14.314 h |
| September, selected | 18.9°C11.2°C | 11.2°C | 123 | 12.4 | 12.613 h |
| October | 14.6°C7.3°C | 7.3°C | 103 | 12.7 | 10.911 h |
| November | 8.8°C2.6°C | 2.6°C | 106 | 13.0 | 9.49 h |
| December | 5.2°C-0.4°C | -0.4°C | 106 | 14.0 | 8.59 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
- Winterthur in SeptemberSwitzerland · 20 kmHigh 18.7°C · Low 10.8°C · 91 mm rain
- Luzern in SeptemberSwitzerland · 40 kmHigh 18.9°C · Low 11.6°C · 166 mm rain
- Konstanz in SeptemberGermany · 57 kmHigh 18.8°C · Low 12.9°C · 94 mm rain
- Sankt Gallen in SeptemberSwitzerland · 62 kmHigh 17.2°C · Low 9.2°C · 127 mm rain
- Basel in SeptemberSwitzerland · 76 kmHigh 20.1°C · Low 10.8°C · 95 mm rain
- Villingen-Schwenningen in SeptemberGermany · 77 kmHigh 16.9°C · Low 8.9°C · 93 mm rain
- Vaduz in SeptemberLiechtenstein · 77 kmHigh 19.1°C · Low 10.5°C · 154 mm rain
- Freiburg in SeptemberGermany · 87 kmHigh 20.0°C · Low 11.8°C · 77 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 Zürich) is explained once on the Zürich year overview and on the Sources, method and limits page.