Characteristics of Cumulonimbus with Waterspout over Ladoga Lake from Remote Measurements

Characteristics of a thunderstorm cloud, from which a waterspout over Ladoga Lake appeared are studied with the use of the measurements from C-band Doppler Meteorological Radar (DMRL-C), a lightning detection system, and a high-altitude atmospheric radiosonde. Analysis of the indices of convective instability showed small to moderate probability of the development of intense convective processes. We applied algorithms for hydrometeor classification and updraft determination from DMRL-C measurements of polarization characteristics for the first time. These algorithms revealed the occurrence of large ice particles in the cloud at the beginning of thunderstorm activity and recorded an extended updraft associated with the waterspout. Analysis of dependences between the lightning frequency and different radar characteristics showed that the correlation is the strongest with a number of large ice particles characterized by the volume of supercooled (above 0°C isotherm) part of the cloud with reflectivity larger than 50 dBZ.