Is Köln hot in September?
Days are typically mild at 20.5°C, while nights average 12.1°C.
Germany · 1991–2020 normal
Typical September weather in Köln: 20.5°C by day, 12.1°C at night, 67 mm of rain over 10.3 wet days. These are measured 1991–2020 station normals, not a forecast.
In the year-round weather comparison, September scores 72 out of 100 (August leads the year at 85). Daylight is calculated as 12 h 33 from latitude 50.93°.
September at a glance
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Days are typically mild at 20.5°C, while nights average 12.1°C.
The measured monthly average is 67 mm across about 10 wet days.
There are about 12 h 33 between sunrise and sunset at mid-month, calculated from the place latitude.
September ranks 4 of 12 in our weather comparison; August ranks first.
The evidence behind this page
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The weather comparison for Köln is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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