ATTEMPTS TO CREATE BALL LIGHTNING WITH TRIGGERED LIGHTNING We describe attempts to create ball lightning by directing lightning, triggered from natural thunderclouds using the rocket-and-wire technique, through a variety of materials. Some of the observed phenomena have features in common with natural ball lightning or with laboratory attempts to create it: flame-like luminosity for up

HIGH‐SPEED VIDEO OBSERVATIONS OF A LIGHTNING STEPPED LEADER High‐speed video images of eight branches of a lightning stepped leader recorded at a frame rate of 300 kiloframes per second (kfps) (3.33 ms exposure) are analyzed, representing the fastest published frame rate measurements of stepped leader stepping by about 1 order of magnitude and the first

GEOMETRICAL AND ELECTRICAL CHARACTERISTICS OF THE INITIAL STAGE IN FLORIDA TRIGGERED LIGHTNING We characterize the geometrical and electrical characteristics of the initial stages of nine Florida triggered lightning discharges using a Lightning Mapping Array (LMA) and measured channel-base currents. We determine initial channel and subsequent branch lengths, average initial channel and branch propagation speeds, and

“CHAOTIC” DART LEADERS IN TRIGGERED LIGHTNING: ELECTRIC FIELDS, X-RAYS, AND SOURCE LOCATIONS We present the first published observations of “chaotic” dart leaders in triggered-lightning discharges. We examine four leaders that exhibited “chaotic” electric field derivative (dE/dt) signatures in their final 10 to 12 ms. The dE/dt signatures were characterized by bursts exhibiting widths of the

THE ATTACHMENT PROCESS OF ROCKET-TRIGGERED LIGHTNING DART-STEPPED LEADERS Time-correlated 1.54 μs high-speed video frames, channel-base current and current derivative (dI/dt), and electric field derivative (dE/dt) measurements are used to analyze the attachment process of triggered lightning dart-stepped leaders. Lengths, speeds, and durations of the upward-connecting positive leaders propagating from the launching structure are measured and