The Relationship between Severe Storm Reports and Cloud-to-Ground Lightning Polarity in the Contiguous United States from 1989 to 1998

Open Access
Publisher Website
Google Scholar
Abstract
The majority (61%) of severe storm reports (i.e., large hail and tornado) during the 1989–98 warm seasons (April–September) were associated with predominantly (>90%) negative cloud-to-ground (PNCG) lightning. Across the contiguous United States, only 15% of severe storm reports were characterized by predominantly (>50%) positive CG (PPCG) lightning activity. However, significant regional variability occurred in the relationship between warm season severe storm reports and CG lightning polarity. In the eastern United States, a significant fraction (81%) of severe storm reports occurred nearby PNCG lightning while only 2% of severe storms were associated with PPCG lightning. The CG lightning behavior was quite different over the northern plains; only 28% of severe storm reports were linked with PNCG lightning while 43% were characterized by PPCG lightning. Although the direct physical relationship is still not evident, this regional variability appears to be at least partially explained by differen... Abstract The majority (61%) of severe storm reports (i.e., large hail and tornado) during the 1989–98 warm seasons (April–September) were associated with predominantly (>90%) negative cloud-to-ground (PNCG) lightning. Across the contiguous United States, only 15% of severe storm reports were characterized by predominantly (>50%) positive CG (PPCG) lightning activity. However, significant regional variability occurred in the relationship between warm season severe storm reports and CG lightning polarity. In the eastern United States, a significant fraction (81%) of severe storm reports occurred nearby PNCG lightning while only 2% of severe storms were associated with PPCG lightning. The CG lightning behavior was quite different over the northern plains; only 28% of severe storm reports were linked with PNCG lightning while 43% were characterized by PPCG lightning. Although the direct physical relationship is still not evident, this regional variability appears to be at least partially explained by differen...