On Wednesday, June 15, 1892, a violent, deadly tornado family swept portions of southern Minnesota, striking several communities, killing a dozen people, and injuring 76. It generated three intense tornadoesâÂÂretroactively rated F3 or stronger on the Fujita scaleâÂÂincluding a powerful F5 that claimed nine lives (the other tornadoes collectively killed three or more others and caused F3 damage). According to tornado expert Thomas P. Grazulis, the twisters were part of a "complex" severe weather event.
Prior to 1990, there is a likely undercount of tornadoes, particularly E/F0âÂÂ1, with reports of weaker tornadoes becoming more common as population increased. A sharp increase in the annual average E/F0âÂÂ1 count by approximately 200 tornadoes was noted upon the implementation of NEXRAD Doppler weather radar in 1990âÂÂ1991. 1974 marked the first year where significant tornado (E/F2+) counts became homogenous with contemporary values, attributed to the consistent implementation of Fujita scale assessments. Numerous discrepancies on the details of tornadoes in this outbreak exist between sources. The total count of tornadoes and ratings differs from various agencies accordingly. The list below documents information from the most contemporary official sources alongside assessments from tornado historian Thomas P. Grazulis.