The 29 June 2000 Supercell Observed during STEPS. Part II: Lightning and Charge Structure

• DOI: 10.1175/jas3615.1
• Publication Date: 2006-01-05T16:07:10Z
• Authors: Kyle C. Wiens; Steven A. Rutledge; Sarah A. Tessendorf
• Keywords: Graupel; Supercell; Lightning; Lightning detection; Atmospheric electricity; Upper-atmospheric lightning

Abstract This second part of a two-part study examines the lightning and charge structure evolution 29 June 2000 tornadic supercell observed during Severe Thunderstorm Electrification Precipitation Study (STEPS). Data from National Lightning Detection Network New Mexico Tech Mapping Array (LMA) are used to quantify total cloud-to-ground (CG) flash rates. Additionally, LMA data infer gross determine origin locations regions involved in CG flashes. The rate reached nearly 300 min−1 was well correlated with radar-inferred updraft graupel echo volumes. Intracloud flashes accounted for 95%–100% activity any given minute. Nearly 90% delivered positive ground (+CGs). first 20 min this storm consisted midlevel negative overlying lower no evidence an upper charge. later (severe) phase more complex but maintained what could be roughly described as inverted tripole, dominated by deep (5–9 km MSL) region produced only two (both positive) 2 h activity, both which occurred brief surge hail production. Frequent +CG began coincident dramatic increases updraft, production, rate, formation F1 tornado. tended cluster or just downwind heaviest precipitation, usually contained hail. all originated between 5 9 MSL, centered at 6.8 (−10°C), tapped LMA-inferred precipitation core (more often) weaker reflectivity extending downwind. All one −CG >9 MSL strike near core.