Wind gusts are short-lasting (3 to 20 seconds) fortified winds with higher speed than the average wind (~ 10 min). They can occur during a front passage or thunderstorms. In particular, cold downwinds in severe thunderstorms are responsible for the largest wind damage and therefore of great interest in the weather forecast. However, the small-scale and short-lived nature of gusts impedes their explicit dissolution in weather models. Therefore, gusts as a sub-scale phenomenon have to be derived from other, resolved model variables. For this purpose, an exact gust detection and a detailed description of the environmental conditions are necessary. Although gusts occur at higher altitudes, previous measurements are typically limited to heights below 10 meters. Therefore, above 10 meters (for example, some meteorological masts) there are only few measurements available to validate and improve models.

The FESSTVaL campaign aims to measure wind gusts, especially at altitudes above 80 m, and to better understand the processes that lead to them. With the help of Wind lidars (light detection and ranging) the wind vector at different heights can be determined by considering the Doppler effect. Wind lidars are a proven and variably applicable method to determine wind profiles up to the upper edge of the mixture layer (about 1-3 km). As part of the FESSTVaL test campaign, various scanning patterns are being tested to find the appropriate configuration to use during the main campaign. Here, the comparison with ultrasonic anemometer gust measurements of the Falkenberg weather mast is decisive. During the main campaign, the focus is then on the synopsis of the different measurements that occur in combination with gusts.