NWC REU 2004
May 24 - July 31



Cloud-to-Ground Lightning Production in Strongly Forced, Low-Instability Convective Lines

Matthew Van Den Broeke, David Schultz, Robert Johns, Jeffry Evans, and John Hales



On 9 November 1998, a convective line initiated over Oklahoma along a cold front in a moderately unstable environment. The line moved east into an area of low to zero instability during 10 and 11 November 1998, yet continued producing damaging surface wind gusts. After moving into weaker instability, the strongly forced, low instability convective line quit producing cloud-to-ground (CG) lightning as detected by the National Lightning Detection Network (NLDN). This paper seeks to explain the evolution of CG lightning in this case, the maintenance of the convective line in a low instability environment, and the production of damaging surface winds. On 9 March 2002, a similar case occurred. Lightning production in this case is documented, and other similarities between this and the 9-11 November 1998 case are noted.

Full Paper [PDF]