Observations of a mesoscale convective system

In this contribution we will document the life cycle of a mesoscale convective system (MCS) as inferred by an operational profiler scan using the polarimetric C-Band radar at Hohenpeißenberg observatory. The profiler scan or birdbath scan is part of the operational scan of the weather radar network operated by the German Meteorological Service (DWD). This scan is primarily used to monitor the absolute calibration and to deduce the offsets of differential reflectivity and phase. This scan is run every 5 min at 0.4 and 0.8 mus pulse width in STAR (Simultaneous Transmit and Receiver) mode, following the operational 5-minute volume. Aside from the monitoring aspects this scan is also interesting from a meteorolgical point of view as it provides detailed information (in time and space) of the dynamics and physics of precipitation events passing over the radar site. On September 10th, 2012, a MCS moved from the Alps northward towards Munich. At the observatoy, close to 50 mm rain were measured in a period of about 4 hours. Over the four hours, the typical structure of a MCS could be observed: the initial convective section, a transition period and then stratiform rain regime. During the convective part of the system hail was reported (8 mm) by weather observers, consistent with the measurements of a on-site present weather sensor. A hail spike signature could be observed, presumably caused by multi-path reflections. Note, that is hails spike is not associacted with large hail. In this paper we will document the features of that event as seen by the doppler moments, the polarimetric moments and the classic radar moments. The analysis of the radar data will be complemented by routine in-situ measurements taken at the Hohenpeißenberg meteorolgical observatory.