Initiation and development of a long-lived, high plains squall line

Few case studies of the initiation and development of long-lived squall lines have been done. In this work, an attempt is made to investigate the initial stages of a squall line that developed on June 21, 1993 over the foothills of the Colorado Rocky Mountains in an environment where the vertical shear of the horizontal wind was weak at low to midlevels but strong at upper-levels. The mesoscale convective system (MCS) produced hail 14 mm in diameter and surface wind gusts to 19 ms^-1 within the first two and a half hours of its existence. This squall line was analyzed using data collected as part of the RAPS-93 experiment. Results were compared to the conceptual model of squall lines advance by Smull and Houze, and Houze et. al.