page_title: Southern Great Lakes Derecho of 1991
section_title: South Dakota
hierarchical_section_title: Southern Great Lakes Derecho of 1991 / South Dakota
caption_attribution_description: English: Map of the Southern Great Lakes Derecho of 1991.
context_page_description: The Southern Great Lakes Derecho of 1991 is the derecho event that occurred on July 7 and 8, 1991. It lasted 17 hours and raced from South Dakota through southern Michigan before dying out over Western Pennsylvania.
context_section_description: This derecho started in southeastern South Dakota at around 8 A.M. CDT.
caption: Map of the Southern Great Lakes Derecho of 1991 (courtesy of NOAA)
exif: {}