Netherlands must brace for far more extreme weather, says Dutch meteorological institute

The KNMI warns in a new report that the Netherlands must be prepared for far more severe weather extremes than it has seen before. Experts sketch out scenarios ranging from intense heatwaves to runaway wildfires and the remnants of hurricanes sweeping across the country. By mapping these risks, they aim to help the government take timely action to make the country more resilient.

“Climate change is often described as a shift in the average, but it is the extremes that have the greatest impact,” the institute explains. Director Maarten van Aalst adds that his “worst nightmare” is being responsible for climate-related disasters for which the Netherlands is not adequately prepared.

Van Aalst cites the thousands of deaths during the 2003 European heatwave and the hundreds of victims of the 2021 Ahr Valley floods in Germany. Zuid-Limburg also faced heavy damage in that disaster, though it was limited to property losses.

In the foreword to An Extreme Report, he warns that such extreme events are intensifying quickly, exposing how unprepared Europe and the Netherlands still are. One scenario in the report examines how Amsterdam would cope with an intense heatwave, with temperatures soaring above 35 degrees Celsius for several consecutive days.

The analysis uses the 2018 heatwave as its baseline, a period that already revealed how vulnerable the Netherlands can be. According to the KNMI, rail lines bent, bridges jammed, metro networks malfunctioned, and road surfaces deteriorated. Water quality dropped sharply, leading to swimming warnings because of blue-green algae, right when people most needed relief from the heat. Even the drinking water system began to strain under the conditions.

A longer, more intense heatwave would dramatically amplify the impacts. Researchers warn that when hot days are followed by warm nights, buildings no longer cool, indoor temperatures stay elevated, and people’s bodies can’t recover, increasing the likelihood of heat-related illnesses, hospital admissions, and excess deaths.

Electricity demand, especially from air conditioning, would surge, putting additional pressure on the power grid and raising the risk of cooling failures in supermarkets, transit systems, and healthcare facilities. Emergency services could struggle to keep up.

These scenarios are meant to help authorities prepare: they can use them to design emergency plans and run stress tests. The core message is that timely, well-planned adaptation offers the biggest benefits for public health and safety.