Tornado outbreak from North Dakota to Kansas, June 7–8, 1984; F5 tornado in Barneveld, WI
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On June 7–8, 1984, a significant severe weather and tornado event took place across the central United States from North Dakota to Kansas. The tornado outbreak produced several significant tornadoes including an F5 tornado which traveled through Barneveld, Wisconsin, in the early hours of June 8. The entire outbreak killed at least 13 people across three states including 9 in Barneveld alone.
Meteorological synopsis.
A low-pressure system entered the Midwestern United States on June 7, 1984, and intensified while bringing a surge of moist and humid air coming from the Gulf of Mexico. After most of the affected areas were hit by a mesoscale convective complex earlier during the morning of June 7, the unstable atmosphere, as well as wind shear and high convective available potential energy (CAPE), produced a favorable environment for the development of extensive severe weather with possible tornadoes. Starting at around mid-afternoon, it started to produce several tornadoes across southern Minnesota and northwestern and southern Iowa including three F3s and a long-track F4 which traveled over from extreme northern Missouri to southwest of Iowa City. That tornado killed 3 people including one in Missouri's Harrison County. Another person was killed in Ringgold County in Iowa by an F2 tornado at around 9:00pm CDT. Activity continued through the overnight hours as a new cluster of storms developed across Wisconsin near the Iowa–Illinois borders and produced strong tornadoes including the Barneveld tornado up until the early morning hours of June 8, 1984, before dissipating. Straight-line winds in excess of and very large hail were also reported in eastern Iowa from the storm that went on to drop the tornado in Barneveld, Wisconsin.
Confirmed tornadoes.
Barneveld–Black Earth, Wisconsin.
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As the tornado activity calmed down across Iowa and Minnesota in which numerous strong to severe tornadoes struck those areas from mid-afternoon to mid-evening, the severe weather shifted east towards Wisconsin after dark where a tornado watch was issued at about 11:00pm CDT. By this time, most of the residents of Barneveld had gone to bed and were unaware of the tornado watch. A supercell thunderstorm, which affected portions of southeastern Iowa with a few tornadoes at around 9:00pm CDT before weakening and intensifying shortly after, entered Wisconsin from the Iowa/Illinois border at around 12:00am CDT near Dubuque. Shortly after 12:30am CDT, June 8, it produced its first tornado near Belmont in Lafayette County and lifted near Mineral Point in Iowa County about fifteen miles southwest of Barneveld.
A few minutes later, this storm system produced one of the few F5 tornadoes to hit Wisconsin, developing northeast of Mineral Point (five to six miles southwest of Barneveld). At 12:41 am CDT this F5 tornado drove through the center of Barneveld in full force, finally dissipating in northern Dane County around 1:40am CDT after traveling for 59 minutes. A strong lightning strike cut the electricity to the town just a few minutes before the tornado struck Barneveld, but it was followed by a deafening clap of thunder that awakened many residents. (It is said that the loss of power prevented the tornado siren from being activated prior to its arrival; in actuality, the town did not have a tornado siren that differed from the siren used to activate the town's volunteer fire and EMT squad. If the siren had been activated, the residents would not have known it was a tornado warning.) At its peak, the tornado was nearly a quarter-mile wide. Other tornadoes rated from F1 to F3 touched down from Columbia County to Dodge County until after 3:00am CDT when activity finally weakened.
The tornado was responsible for nine deaths and nearly 200 injuries in Barneveld while causing about $25 million in damage. In total, all three churches (the Congregational United Church of Christ, the Lutheran Church, and the Roman Catholic Church), 93 homes and 17 out of the 18 businesses in town (including the library, municipal building, fire station, bank, and post office) were all destroyed. The village's water tower, though damaged, was not toppled by the winds. In addition, 64 other homes were badly damaged. The F5 damage occurred at a cul-de-sac on the northeast side of town. A cluster of newly built homes were completely swept away at this location. Trees were debarked and vehicles were thrown and mangled. Some of the debris including paperwork was later found about 135 miles away from the village. Eight homes were also destroyed in Black Earth, and 24 additional homes were destroyed between Barneveld and Black Earth. Other tornadoes in Wisconsin caused two additional injuries and about $15 million worth of damage but no additional fatalities.
The National Weather Service in Madison reported the next day that the frequency of lightning flashes in the storm exceeded 200 per minute. The flashes produced a strobe-like effect, as mentioned in media reports and books about the disaster.
Historical perspective.
The Barneveld tornado became the most recent F5/EF5 tornado to touch down at night. Group members prior to Barneveld included the Blackwell, Oklahoma and Udall, Kansas tornadoes during the 1955 Great Plains tornado outbreak; the tornado that struck downtown Lubbock, TX in 1970; and the Tanner and Guin, Alabama tornadoes from the 1974 Super Outbreak. Later, the Birmingham tornado in April 1998 and the Greensburg tornado in May 2007 also joined that group of violent nighttime tornadoes. As it was in Barneveld, people in these other communities may not have been aware of incoming severe weather nor would they be able to see the tornado until it was already upon them, which increased their odds of injury or death.
The Barneveld tornado was the only F5-rated storm in the United States in 1984 and the first to strike Wisconsin since the Colfax tornado killed 21 people in 1958. While it had been 26 years since the last F5 tornado struck Wisconsin, it had only been two years since the last F5 tornado in the United States; thankfully, while the Broken Bow, Oklahoma tornado of April 1982 injured 29 people, it didn't take any lives.