The Barneveld Tornado

On a night when the winds were howling across southern Wisconsin, many headed to bed unsuspecting of the tragedy that would unfold during the early morning hours on June 8th, 1984. 

Between 12:40am and 1:40am, a violent tornado developed across eastern Iowa County and tracked northeast across northwest Dane County. This tornado, later known as the Barneveld Tornado, was the second tornado produced by the supercell thunderstorm as it tracked across southern Wisconsin, and wouldn't be the last tornado it produced. 

We will take a closer look at the event below, including how the atmospheric setup evolved and timeline of events.

A volatile atmospheric setup led to an outbreak of tornadoes on June 7-8, 1984, stretching from northeast Kansas up into eastern North Dakota and Wisconsin. The most significant severe weather occurred from Iowa, northeastward into Southern Minnesota and Southern Wisconsin. 

To the right is a sounding taken on the evening of June 7, 1984 from the NWS Green Bay forecast office, courtesy of the University of Wyoming sounding archive website. To highlight the temperature and dew point temperature vertical profiles better, they are highlighted in red and green, respectively. There was a pocket of surface based instability, with around 1000 J/kg, highlighted by the yellow area on the sounding. Wind barbs, to the right of the sounding, show impressive kinematics were in place, with a very dynamic environment setting up across Wisconsin that evening on the evening of June 7, 1984.

A total of 46 tornadoes occurred, including a violent long-track tornado that traveled 134 miles from far northern Missouri up across south-central Iowa on June 7th, followed by the infamous F5 tornado that tracked across parts of Iowa and Dane counties in southern Wisconsin early in the morning on June 8th. 

The map shown to the right is a composite image with several severe weather ingredients overlaid, which depicts the conditions around 7 PM on June 7, 1984. Please note that some smoothing and estimations were used in the production of that graphic.

Shaded in purple, blue, and yellow are the varying levels of instability ahead of the low pressure system, based on the actual observed lifted indices. You can see that the axis of best instability encompassed most of Iowa, Southeastern Minnesota and Western Wisconsin at 7 PM, on the evening of June 7, 1984. The white lines are upper level streamlines, showing the direction of the wind flow in the upper levels of the atmosphere. Finally, the black shaded and scalloped area is the approximate location of a very strong upper level jet streak.

Vertical wind shear, the difference in wind speeds, and wind direction, between the upper levels of the atmosphere and the lower levels of the atmosphere, was maximized underneath the strong jet streak. The tornado outbreak occurred about where the strongest wind shear and most unstable air mass overlapped.

The main surface front at approximately 10 pm on June 7, 1984, or about 3 hours prior to the "Barneveld tornado". The storms, at that time, were progressing across Northwest and West-Central Wisconsin, and stretched back through Eastern Iowa and into Northern Missouri. This means that the storms were moving across a very warm, humid, and unstable air mass as they approached Wisconsin. With abundant energy, and strong vertical wind shear, the storms continued to produce significant severe weather well after dark.

A tornado watch is issued for south-central Wisconsin, including Dane County. 

The tornado watch was issued by The National Severe Storms Forecast Center (NSSFC) in Kansas City, Missouri. In 1997, the NSSFC, which is now known as The Storm Prediction Center, moved to Norman, Oklahoma.

The animation below shows the progression of tornado watches across the Midwest that night.

Between 12:52am and 12:55am, reports of strong winds, hail, and frequent lightning began to come in from Sauk, Iowa and Dane County. There were reports of trees down in the Barneveld and Black Earth areas. It was unknown at the time, but these reports of trees down were caused by the Barneveld Tornado. 

1:10am, a tornado warning was issued for portions of Dane County as the storm continued to track northeast early that morning.

Around 1:26am, reports of homes destroyed in the Black Earth area began to come in.

Around 3:03am, reports of injuries from the Barneveld area and mentions that a possible tornado had gone through town. The tornado would later be verified, and ranked a F5 on the Fujita Scale.

The aerial photo on the right shows the path of destruction left behind after the F5 tornado tore through the heart of Barneveld. This image was taken by Bob Rudolf and is courtesy of the  University of Wisconsin-Madison Library  and can be found under the following collections: The State of Wisconsin collection, Wisconsin Local Histories, and the Barneveld Local History Collection.

To this date, the "Barneveld Tornado" remains the second costliest tornado, based on official damage costs, in Wisconsin history with total damage estimated at $40 million. 90% of the Village of Barneveld was destroyed by the tornado, which was estimated to have been 450 yards wide with winds over 300 mph. The supercell thunderstorm that produced the Barneveld tornado was so strong that it lofted and carried debris from the town, and scattered it across central Wisconsin.

The Oakfield Tornado on July 18, 1996 remains the costliest tornado in state history, with total estimated damage costs at $40.4 million.

The image on the right shows how the debris from the Barneveld tornado was scattered across central Wisconsin as the supercell thunderstorm continued to track northeast during the early morning hours on June 8th, 1984. ​

The Barneveld Tornado was one of many that impacted the Midwest, from far northeast Kansas up across Iowa and into southern Wisconsin and Minnesota. Use the interactive map below to explore the other tornadic activity that occurred across the heart of the country on June 7-8, 1984.

6 additional tornadoes occurred in southern Wisconsin during the early morning hours on June 8, 1984. This included four F2 tornadoes, one F3 tornado, and one F1 tornado. Including the Barneveld Tornado, 7 tornadoes tore across southern Wisconsin early that morning. Many of these tornadoes spawned from one supercell thunderstorm, which cycled numerous times to produce these tornadoes. This is what we refer to as a classic cyclic supercell, which is defined as the following by the old NOAA Technical Memorandum NWS SR-145:

In total, there were 43 tornadoes that developed during the tornado outbreak from June 7-8, 1984. This included a long-track F-4 tornado that developed in north-central Missouri and tracked all the way into eastern Iowa. It was on the ground for a total 127 miles! Looking for more information about the Iowa portion of this tornado outbreak? Download the NOAA Overview Document  here . 

The lives of many were changed that night. 200 people were injured and tragically, 9 people lost their lives that night. 

The collection of photos below show the damage caused by the F5 Barneveld Tornado. Photos of the damage are courtesy of the Wisconsin State Journal and NWS Milwaukee/Sullivan.

Here is the original Public Information Statement issued following the devastating tornado outbreak during the early morning hours on June 8th, 1984 is shown to the right. The Barneveld Tornado was on the ground for nearly one full hour, tracking 36 miles across portions of Iowa and Dane counties. 

Tornadoes that occur during the overnight hours are particularly dangerous, because they're incredibly difficult to spot. During daylight, tornadoes are easily spotted. At night, tornadoes can be incredibly difficult to spot, relying on quick bursts of lightning or power flashes to illuminate the tornado. Another reason nighttime tornadoes are dangerous is they often occur when most people have gone to sleep. 

Remember, outdoor sirens are NOT designed to wake you up in the middle of the night. This is why we say it's important to have multiple ways to receive warnings and a way that will wake you up in the middle of the night if you're sleeping and a tornado warning is issued! It could save your life.

In 1971, Dr. T. Theodore Fujita introduced a damage scale used to estimate the intensity of tornadoes. This damage scale, known as the Fujita Scale, or F-Scale, ranked tornadoes from F-0 to F-5 with wind speeds and the degree of damage increasing from light to incredible. 

In 2007, improvements were made to the Fujita Scale with the implementation of The Enhanced Fujita (EF) Scale. The EF-Scale still incorporates the degree of damage, but takes into account what was damaged through the use of Damage Indicators (DIs). For example, softwood trees are more flexible and typically require stronger winds to snap or cause damage, compared to hardwood trees. When it comes to buildings that sustain damage, the EF-Scale takes into account what type of construction or building was impacted and how well it was built and/or anchored.

For more discussion related to the Fujita and Enhanced-Fujita Scales, please visit The Storm Prediction Center's website on the  transition to the Enhanced Fujita Scale.  More information about the Enhanced Fujita Scale itself can be found online,  here .