How much hotter is your German hometown than it was in 1961?

A map developed by FOCUS using data from the German Weather Service (DWD) lets residents see how many heat days their town or city has today compared with the 1960s, 1990s and 2010s.

Heat days and heatwaves are increasingly regular

Since the 1960s, the number of heat days (Hitzetage) per year in Germany has generally increased. A day is considered to be a “heat day” when temperatures reach at least 30 degrees celsius.  

Between 1961 and 1990, there was an average of 6,3 heat days per year recorded at DWD measuring stations across Germany. Between 1991 and 2020, the annual average increased to 21,1 heat days. Between 2021 and 2025, the annual average shot up to 34 heat days, nearly five times as many as in the period between 1961 and 1990.

“It is incorrect to suggest that [recent] heatwaves [...] are merely isolated incidents that have also occurred in the past, as the data show,” Rüdiger Glaser, professor of physical geography at Freiburg University, told Tagesschau during a 2025 heatwave.

“Particularly over the past 15 years, these extremes have increased in a way that we have not seen before. [...] And the only explanation for this is man-made climate change,” Glaser continued.

How many heat days has your city seen?

A closer look at the FOCUS map, which uses DWD data, reveals that measuring stations in southwestern Germany have seen the biggest increase in the annual number of heat days between 1961 and today. 

The Echterdingen station in Stuttgart recorded an annual average 4,6 heat days between 1961 and 1990, 9,9 days between 1991 and 2020 and 12 days between 2021 and 2025. The Freiburg station 01443 recorded an average of 9,8 heat days between 1961 and 1990, 19,7 between 1991 and 2020 and 21,2 between 2021 and 2025.

However, it is the measuring station at Neckar-Odenwald, also in Baden-Württemberg, which has seen the greatest average increase of all stations across Germany. An annual average of 3,1 heat days was recorded at the station between 1961 and 1990, 10,6 days between 1991 and 2020 and 17 days between 2021 and 2025.

Data for some stations may be incomplete because the station was either opened after a specific timeframe ended or closed before a timeframe began. To see the map in full, head to the FOCUS website.