September 2025: One of the warmest months in 259 years!

September 2025: One of the warmest months in 259 years!

September 2025 will go down in history as one of the warmest September months on record. Loud Small newspaper Compared to the average values ​​for the climate period from 1991 to 2020, the month was 1.4 degrees too warm in the lowlands of Austria and even 1.8 degrees in the mountains. With 18th place in the 259-year history of measurements and 19th place in the 175-year series of mountain measurements, this September is one of the 20 warmest ever.

Around 90 percent of all September months were cooler than September 2025. A notable feature of this September was the summer days, of which a total of 12 were recorded. The average for this period was just 6 summer days. A record was attempted in 2023 with 21 summer days, but the current September has very clearly exceeded this number with 12.

Different weather conditions

September 2025 was marked by extreme meteorological contrasts. Before the start of autumn, temperatures of over 30 °C were recorded; the highest temperature of 32.6 °C was measured in Pabstorf on September 20th. However, from September 22nd the temperatures fell significantly. With a mean temperature of 14.5 °C, this value was 1.2 °C above the 1961-1990 average and 0.7 °C above the 1991-2020 average, as DWD reported.

Rainfall this month was 86 l/m², which is 41% above the 1961-1990 average and 32% above the average rainfall for the last 30 years (1991-2020). In some regions, such as Saarland with 170 l/m², this September was the wettest since 1881. In contrast, some areas in Austria, such as around Kufstein and Kitzbühel, recorded severe drought with a decrease of 35 to 55 percent compared to the long-term average.

Changing climate

The extreme weather conditions and the trend change towards higher temperatures cannot be viewed in isolation from the effects of climate change. Historically, human activities such as industry and transport, as well as changes in land use, significantly influence the climate. How on DWD As illustrated, our climate today is significantly higher in temperature than it has been in the last 2,000 years, and at a rate that is progressing much faster than in the past.

Future emissions will continue to influence global warming. Forecasts indicate that Germany can expect a temperature increase of 3.1 °C to 4.7 °C between 2071 and 2100. September 2025 could therefore not only have been a record month, but also serve as a reminder of the need for rigorous action against climate change.