A proposed microburst nowcasting procedure using single-Doppler radar

Abstract

Descending reflectivity cores, increasing radial convergence within cloud, rotation and reflectivity notches were found to be microburst precursors, appearing typically 2-6 min prior to initial surface outflow. Descending maximum reflectivity cores coincident with increasing radial convergence within cloud (3-8 km AGL) or near cloud base is believed to be a good indicator of storm downdraft and microburst predictor, especially when coupled with low θe air above cloud base and a dry adiabatic lapse rate below cloud base. Three conceptual models have been drawn, based on the 31 events, to summarize the radar signatures of importance in low, moderate, and high-reflectivity microburst-producing storms. -from Authors