Part of thetornadoes and tornado outbreaks of 1892
On Wednesday, June 15, 1892, a violent, deadlytornado family swept portions of southern Minnesota, striking several communities, killing a dozen people, and injuring 76. It generated three intense tornadoes—retroactively rated F3 or stronger on the Fujita scale—including a powerfulF5 that claimed nine lives (the other tornadoes collectively killed three or more others and caused F3 damage). According to tornado expertThomas P. Grazulis, the twisters were part of a "complex"severe weather event.[1]
Prior to 1990, there is a likely undercount of tornadoes, particularly E/F0–1, with reports of weaker tornadoes becoming more common as population increased. A sharp increase in the annual average E/F0–1 count by approximately 200 tornadoes was noted upon the implementation ofNEXRADDoppler weather radar in 1990–1991.[2][note 2] 1974 marked the first year where significant tornado (E/F2+) counts became homogenous with contemporary values, attributed to the consistent implementation ofFujita scale assessments.[6][note 3] 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 historianThomas P. Grazulis.
2+ deaths – This was the first member of a long-lived tornado family in south-central Minnesota this day. It first wrecked a farmhouse, killing a few children inside, and then shattered a schoolhouse, tossing books 1 mi (1.6 km) away; at the school it injured a teacher and 16 pupils, some critically, possibly causing a fatality. It also destroyed a home nearWelcome before dissipating. In all 23 injuries occurred.[1][16]
9 deaths – An exceptionally violent tornado swept away several farmsteads, throwing large timbers from homes up to 3 mi (4.8 km) away and spearing them into the ground. According to Grazulis, it "obliterated" entire homesites at F5 intensity, killing seven people in the Minnesota Lake–Easton area. It then killed a few more people and caused F4 damage in theHartland–Wells area. 45 injuries occurred.[1][16][17]
^Historically, the number of tornadoes globally and in the United States was and is likely underrepresented: research by Grazulis on annual tornado activity suggests that, as of 2001, only 53% of yearly U.S. tornadoes were officially recorded. Documentation of tornadoes outside the United States was historically less exhaustive, owing to the lack of monitors in many nations and, in some cases, to internal political controls on public information.[3] Most countries only recorded tornadoes that produced severe damage or loss of life.[4] Significant low biases in U.S. tornado counts likely occurred through the early 1990s, when advancedNEXRAD was first installed and theNational Weather Service began comprehensively verifying tornado occurrences.[5]
^abTheFujita scale was devised under the aegis of scientistT. Theodore Fujita in the early 1970s. Prior to the advent of the scale in 1971, tornadoes in the United States were officially unrated.[7][8] Tornado ratings were retroactively applied to events prior to the formal adoption of the F-scale by theNational Weather Service.[9] While the Fujita scale has been superseded by theEnhanced Fujita scale in the U.S. since February 1, 2007,[10] Canada used the old scale until April 1, 2013;[11] nations elsewhere, like the United Kingdom, apply other classifications such as theTORRO scale.[12]
^All dates are based on the localtime zone where the tornado touched down; however, all times are inCoordinated Universal Time and dates are split at midnightCST/CDT for consistency.
^The listed width values are primarily the average/mean width of the tornadoes, with those having known maximum widths denoted by ♯. From 1952 to 1994, reports largely list mean width whereas contemporary years list maximum width.[13] Values provided by Grazulis are the average width, with estimates being rounded down (i.e. 0.5 mi (0.80 km) is rounded down from 880 yards to 800 yards.[14][15]
— (July 1993).Significant Tornadoes 1680–1991: A Chronology and Analysis of Events.St. Johnsbury, Vermont: The Tornado Project of Environmental Films.ISBN1-879362-03-1.
