Mesoscale and Radar Analysis of the 30 June 1998 Supercell

On 30 June 1998 an intense squall line swept the central-eastern PO valley: large hail, damaging winds and a supercell were observed with these storms. The forcing due to a baroclinic wave disturbance created the synoptic conditions favourable for storm development. A mesoscale analysis, conducted using the Local Analysis and Prediction System (LAPS), shows the characteristic circulation in the wind field close to the ground from the western and the eastern borders of the PO valley, advecting humidity and increasing the wind shear. Moreover, analysis of temperature and humidity permits to follow movement of the system its across the valley. Reflectivity and Doppler wind fields observed by the C-band radar located at S. Pietro Capofiume, near Bologna, document the position and the intensity of precipitation and the strong rotational pattern associated with supercell. Dual polarisation permits to infer characteristics on the type of the hydrometeors.