ELECTRICAL STRUCTURE IN THUNDERSTORM CONVECTIVE REGIONS - 2 - ISOLATED STORMS

Electric field (E) soundings through the convective regions of two typ es of isolated thunderstorms are examined. Analysis of seven soundings through strong updrafts of isolated supercell storms show that the ba sic E structure there has three \El peaks: a positive peak near 8 km h eight, a negative peak near 10.5 km, and a positive peak near 12 km. S trong updraft soundings are those with average balloon ascent rates in excess of 10 m s(-1). The basic charge structure in strong updrafts o f supercells has four charge regions of alternating polarity. The lowe rmost charge is positive, between about 4 and 8 km, and the uppermost region is negative. Ail the supercell updraft soundings are incomplete due to balloon burst or lightning-induced instrument destruction belo w cloud top. Six supercell soundings that ascended outside strong updr afts are used to show that the E and charge structures there are more complex than within the strong updrafts. Analysis of 15 new or previou sly published soundings through small, New Mexican mount;lin thunderst orms indicates that the basic E structure in or near their convective cores consists of three \El peaks: a lower positive peak at about 5 km height, a midlevel negative peak near 6.5 km, and an upper positive p eak near 9.5 km. The basic charge structure near the center of New Mex ican storm convection has four charge regions, alternating in polarity , with a positive charge region lowest. Soundings in New Mexican conve ction that did not ascend near the convective cores show more complex E profiles and charge structures.