A row of poplars near the KNMI weather radar in Herwijnen has disrupted rainfall forecasts for parts of Gelderland. The trees block radar pulses, meaning actual rainfall may be higher or lower than indicated in weather apps. The affected area runs from Herwijnen towards Germany, between Arnhem and Nijmegen and over Doetinchem.

The KNMI requested pruning late last year, but West Betuwe municipality has not permitted intervention pending research into whether the trees serve as a bat foraging area or flight route, which would be protected. The study has been completed and its results are expected shortly. Meanwhile, the KNMI applies corrections using higher-altitude scans and data from other radars in the Netherlands, Belgium and Germany, but says reducing the disruption remains desirable.