Heat alarm in Krefeld and Viersen: That's how dangerous the index is!

Heat alarm in Krefeld and Viersen: That's how dangerous the index is!

On June 16, 2025, the results of the current heat check by German Environmental Aid were published. The cities of Krefeld and Viersen were found to be moderately affected by heat stress. The heat impact index is particularly noteworthy: Krefeld achieved a value of 14.25, while Viersen was just behind with 14.21. These figures make it clear that both cities have an urgent need for action to better meet the demands of high temperatures. According to Welleniederrhein.de, the expansion of green spaces and the unsealing of areas are particularly crucial in order to increase the quality of life of the residents.

But Krefeld and Viersen are not alone. Mönchengladbach, Neuss and Meerbusch are also currently in the “orange zone” of the heat impact index. Interestingly, no city in North Rhine-Westphalia is in the red zone, indicating some scope for improvement. The evaluation of the cities is based on the criteria of sealing, surface temperature, green volume and population density. This systematic recording, which for the first time uses a “heat impact index”, shows that over 12 million people in German cities are exposed to extreme heat stress, as duh.de reports.

Growing heat stress

The heat stress in our cities is increasing, and not without reason: climate change has something to do with it. This development not only has an impact on the well-being but also on the health of the residents. The need for adaptation measures to ensure tolerable living conditions for all people is urgent. Questions about prevention and increasing heat resilience are therefore the focus of urban development policy, as nationale-stadtentwicklungspolitik.de explains.

A total of 190 cities with more than 50,000 inhabitants were examined for the heat check. A large number of cities were given different “cards”: 31 cities received a red card due to extreme heat stress, 131 received a yellow card, and 28 cities received a green card. These results are based on extensive satellite data that were evaluated together with Potsdamer Luftbild Umwelt Planning GmbH. It is becoming clear that cities are changing and a rethink is necessary in order to better cope with future heat waves and to ensure the quality of life of their residents.

The appeal to the municipalities is therefore unmistakable: More green, less sealing - because with a little more plants and natural areas the cityscape can not only be beautified, but can also make an important contribution to combating the heat. The heat check puts its finger on the wound: action is now required!