Evolution of Two Tornadic Supercells into an Intense Bow Echo Over Southwest211 Nebraska and Northwest Kansas

摘要

On August 21, 1997, two tornadic supercells formed in southwest Nebraska, merged,211u001ethen moved rapidly into northwest Kansas as a bow echo system. Prior to the 211u001emerger, the two storms produced a 4.5 cm (1.75 in) diameter hail just before 211u001ecrossing the Kansas/Nebraska state line. After the storms evolved into the bow 211u001eecho, wind damage became more pronounced and widespread as the system moved 211u001erapidly southeast across portions of northwest Kansas. Although there were some 211u001edifferences during the mesocyclonic stage, the event was similar to one that 211u001eoccurred near Lahoma, Oklahoma in 1994 (Conway 1994). This study will examine the 211u001eenvironmental conditions, radar signatures, and structural damage associated with 211u001ethe event.