Date of Award




Document Type

Master's Thesis

Degree Name

Master of Science (MS)


Department of Atmospheric and Environmental Sciences

Content Description

1 online resource (xiv, 121 pages) : color illustrations, color maps.

Dissertation/Thesis Chair

Lance Bosart

Committee Members

Brian Tang


derecho, MCS, synoptic, Storm winds, Convection (Meteorology), Windstorms, Wind damage

Subject Categories

Atmospheric Sciences


Progressive derechos are severe mesoscale convective systems that often form east of the Rocky Mountains during the warm season (May–August) and cause, by definition, straight-line wind damage along paths upwards of 400 km long. This study develops a subjective, seven-category classification scheme that spans the spectrum of progressive derecho formation environments from those dominated by robust upper-level ridges to those characterized by vigorous upper-level troughs. A climatology of 256 progressive derecho events is created for 1996–2013 and is categorized according to the developed classification scheme. Derecho initiation-relative composites are constructed for each of the seven groups using 0.5° Climate Forecast System Reanalysis data to document the environmental characteristics unique to each group as well as those shared among them. Finally, two in-depth case studies and five cursory case studies provide examples of the seven categories and reveal important nuances in mesoscale dynamic and thermodynamic structure inherent to all derecho cases.