Summer 2026 becomes hottest on record in the Netherlands

The Netherlands is heading toward its hottest summer since national temperature records began in 1901, with August not yet over. Data from the Royal Netherlands Meteorological Institute (KNMI), cited by NOS, show that the average temperature this summer in De Bilt has reached 19.3°C, surpassing the previous record of 18.9°C set in 2018.

The summer has been marked by prolonged heat and severe drought. In June, KNMI issued its first-ever red weather warning for extreme heat, while particularly southern parts of the country experienced repeated heatwaves.

River levels also fell to record lows. Although rainfall last week provided some relief, water levels are expected to take months to recover.

Record heat across the country

KNMI climate expert Peter Siegmund said the Netherlands experienced an unprecedented number of days with temperatures above 35°C, as well as the highest number of tropical days ever recorded.

The country also saw an exceptional number of consecutive nights when temperatures remained at or above 22°C.

“What really surprised me is that it all started in June, which is normally the least warm month of summer,” Siegmund told NOS.

He noted that average summer temperatures in recent years have frequently exceeded the trend projected under the KNMI’s highest climate scenario for 2050.

According to Siegmund, the pace of summer warming is currently roughly in line with that high-end scenario.

“If this continues, what we are experiencing now could be an average summer around 2050 in terms of temperature,” he said.

Siegmund’s calculations suggest that summers of this intensity could currently occur roughly once every five years. As global warming continues, however, the interval between such extreme summers is expected to become shorter.

Warm seas raise concerns for autumn

It remains unclear whether the exceptionally hot and dry summer will be followed by an unusually extreme autumn.

Dutch autumns have generally become warmer and wetter over the past century. The North Sea is currently exceptionally warm, which could contribute to heavier rainfall and intense showers in the coming weeks.