Doppler wind lidar measurements during a thunderstorm at Cabauw, The Netherlands

The Royal Netherlands Meteorological Institute (KNMI) operates several ground-based Doppler lidars, which are laser-based remote sensing instruments to measure wind. We deploy long-range scanning Doppler lidars at our atmospheric research site Cabauw (Vaisala Windcube200S) since 2021 and at Amsterdam Schiphol Airport (Leonardo Skiron3D) since 2025, after a two-year deployment at Cabauw. Together with Rijkswaterstaat (RWS) we operate a network of short-range Doppler lidars (ZX lidars ZX300M) on the North Sea, on TenneT substations within offshore wind farms. Our Doppler lidars are based on infrared laser light and rely on aerosol scattering. As such, the wind measurements are typically bounded to the atmospheric boundary layer and are limited by (optically dense) clouds. The short-range Doppler lidars provide wind profiles up to a height of 300m.

The Doppler lidar instruments allow for unattended and continuous 24/7 operation and data is collected in near-real time.  This enables the use of this data to forecasters for nowcasting, for data assimilation into numerical weather prediction models and for research purposes. These instruments can operate during severe storms, in which they can provide information of the wind field below the cloud base. Furthermore, Doppler lidars can provide boundary layer wind profiles prior to such storms, which could lead to better forecasting of those storms.

Here we present an example of Doppler lidar measurements during a severe convective weather event of 9th of July 2024, a day at which KNMI issued an orange weather warning (“code oranje”) for the whole of the Netherlands. At the time both long-range scanning Doppler lidars were operational at Cabauw. The Skiron3D was performing Velocity Azimuth Display (VAD) scans providing vertical profiles of horizontal wind speed and direction with a range resolution of 25m and 100m respectively with an update frequency of approximately 3 minutes. The Windcube200s was performing continuous vertical velocity measurements with a temporal resolution of 1 s and a vertical resolution of 75m. 

On radar imagery and lightning detection system is observed that the showers and lightning arrives at 17:10 UTC. Signs of approaching severe weather are already visible in the Doppler lidar data starting at 15:00 UTC, indicated by a growing layer with a differing wind direction. Strong updrafts are observed shortly before the arrival of the showers. Heavy rainfall obscured the lidar measurements only for a very short period, such that valuable information can be derived from the lidar measurements before, during and after the storm.