The genesis stage of Tropical Cyclone Oliver during TOGA COARE was studied from two high-flying NASA aircraft bearing a variety of remote sensors on 4 February, 1993 over the Coral Sea. These instruments included a downward-looking Cloud Lidar System, Advanced Microwave Precipitation Radiometer and a Lightning Instrument Package on board the ER-2 (flying at 20 km); and the Airborne Rain Mapping Radar, dropsondes and lightning sensors on the DC-8 (11-12.5 km). This suite of sensors provided a unique examination of the relationship between the degree of cloud electrification/lightning generation, vertical reflectivity structure and ice scattering signatures of deep convective towers in both the eyewall-forming region and a major rainband of a tropical cyclone during genesis. Lidar detected the deepest convective towers, penetrating to 18 km altitude, within Oliver's primary rainband and nearly 200 km from the center, while maximum cloud tops of 16 km were found within the radius of maximum wind, close to the nascent eye. Numerous instances of lightning were associated with the deepest towers, along with the presence of liquid water at temperatures below -40 C. The eye region deep convection, while lacking detectable lightning discharges, did on numerous occassions generate strong electrical fields. The vertical radar structure of highly-sheared rainband convection shows ample evidence of large reflectivities lofted well into the mixed phase region, with values of 30-35 dBZ present up to 10 km altitude. A strongice-scattering signature in the 85 GHz passive microwave channel further corroborates the highly electrified nature of this convection. Simulations using a time-dependent, one-dimensional cloud model with sophisticated microphysics and an electrification parameterization reveal early electrical breakdown in the rainband convection, and only marginal lightning production in the innercore region. These differences are related primarily to updraft strength and evolution. While these simulations further show that the deepest latent heat release occurred within the outer rainband convection, its effects on the intensifying storm were probably minimal; the 16-km deep towers close to the core alone are shown to account for the observed surface pressure fall