First fully sub-zero "ice day" recorded in over two years in the Netherlands
After an unprecedented 762 days without an "ice day," meteorologists in the Netherlands recorded the first such event on Saturday. According to Weeronline, the temperature in De Bilt, Utrecht, remained below freezing for a full 24 hours, never rising higher than a maximum of -0.7 degrees Celsius. The city is considered a central average for the weather in the Netherlands, and the weather station there serves as the basis for national records.
The last official ice day occurred on December 17, 2022, in De Bilt, which is also home to Dutch meteorological institute KNMI. In both 2023 and 2024, the temperature never remained below freezing for an entire day from midnight-to-midnight, the requirement for the "ice day" designation. The closest occurrence was on January 21, 2023, when the temperature reached 0.1 degrees, and on January 17, 2024, when it was exactly 0.0 degrees.
The KNMI attributes the decline in ice days to climate change. In a recent report, the weather institute noted that since the 1960s, the number of ice days in the Netherlands has been steadily decreasing. While the average number of ice days per year in the 1960s was 11, it has now dropped to just three. This trend reflects an average reduction of 1.5 ice days per decade.
"We not only see fewer ice days, but they are also less cold," stated the KNMI. The last time temperatures stayed below -10 degrees, which qualifies as a severe ice day, was on January 14, 1987. The coldest ice day of the current century occurred on December 2, 2010, when the temperature in De Bilt did not exceed -6.1 degrees.
In addition to climate change, shifting wind patterns have played a role in the decline of ice days. According to the KNMI, winds in recent years have less frequently originated from the cold northeast and more often come from the milder west. The cause of this shift remains unclear, making future predictions about the frequency of ice days uncertain.
Despite the lack of ice days in De Bilt over the past two years, some localities in the Netherlands recorded such events. On December 28, 2024, Hoogeveen experienced an ice day with a maximum temperature of -0.3 degrees, while Heino in Overijssel reached -0.1 degrees. Additionally, regional ice days were observed on January 11 and January 17, 2025, in various parts of the country.
