Forecasting and nowcasting convective weather phenomena over southern peninsular India - Part II: Severe local storms

A few case studies of severe thunderstorms especially hail storms, over Chennai and its neighbourhood within 250 km radius that occurred during 2002-2007 have been analysed in this paper. Pre-convective thermodynamic parameters have been computed using Chennai, Karaikal, Bangalore, Machilipatnam and Hyderabad RS/RW data; and empirical thresholds that are in vogue have been validated for the hail storms reported by print and electronic media. Hail stone size estimation has been attempted using build 9 algorithm of NEXRAD, USA and found to be working well for the tropical environment as well. The necessity of feedback from the public in timely reporting severe storms with precision and accuracy has been stressed for developing a database to fine tune the hail warning and hail stone size estimation algorithms.