9321361 Rutledge Collections of thunderstorms known as mesoscale convective systems (MCS) are of scientific interest for a variety of reasons. MCSs are a major source of rainfall and severe weather (including lightning). In addition, they are believed to be important to the vertical redistribution of atmospheric heating which is important to global dynamics. This research will focus on studying the dynamical, thermodynamical and electrical properties of deep convection. Both mid-latitude and tropical convection will be studied using data from previously completed field campaigns. Results of this research will increase knowledge of storm electrification, especially the linkages between electrification, cloud dynamics and mircrophysics. The Principal Investigator will continue ongoing studies on the structure of (MCSs) in both the mid-latitudes and tropics. Data from the new National Weather Service Doppler Radars (WSR-88D) will be used to study the structure and evolution of mid-latitude MCSs.