Tornado outbreak sequence of June 3–11, 2008

Tornado damage in Rush County, Indiana

Damage in Rush County, three years after the storm

Several clusters of thunderstorms developed during the morning from eastern Nebraska across Iowa into Illinois, taking place along a warm front. The front remained over the same areas during the day, as daytime heating and southwesterly surface winds brought warm and unstable air northward, resulting in severe weather development. The presence of strong winds aloft aided in development of multiple clusters and lines of thunderstorms that produced damaging wind, hail and tornadoes across Missouri, Illinois and Indiana.[2]

A moderate risk of severe weather was issued by the Storm Prediction Center for parts of Indiana, Kentucky, Illinois, Ohio and West Virginia on June 3,[3] Two particular tornadoes, rated EF2 and EF3 on the Enhanced Fujita Scale, caused extensive damage across portions of central Indiana.[4] The EF3 tornado damaged 34 structures in Rush County, of which 27 of them were in Middletown. Eight people were injured in Rush County, including a 67-year-old woman who was impaled in the chest by a large tree limb and later died as a result of her injury on August 17.[5] A 19th century landmark covered bridge in Moscow was destroyed,[6] as well as severe damage to dozens of homes, including some that were swept completely off the foundation. The EF2 tornado damaged 20 to 30 homes in Brown County, 40 buildings at Camp Atterbury in Johnson County and 59 buildings in Edinburgh.[5]

A moderate risk of severe weather was issued for northern Kansas into southern Nebraska and from eastern West Virginia through Virginia, Maryland and Delaware.[7] An ongoing line of thunderstorms moved east across West Virginia as the atmosphere began to destabilize. The thunderstorms resulted in a threat for isolated tornadoes in eastern sections of West Virginia, Virginia, Delaware and Maryland. In the central Great Plains region, a warm front extended northeast in northeastern Kansas from a surface low in central sections of Kansas. Strong instability occurred in the vicinity of the area as a result of surface heating. An intensifying low-level jet stream broke the cap in the region and resulted in the development of thunderstorms.[8] During the afternoon, numerous thunderstorms formed across the Mid-Atlantic States. An EF0 tornado was produced from one of the thunderstorms that impacted portions of Chesapeake Beach, tearing off sections of roof and siding from 10 to 20 single family homes. EF1 tornadoes were produced in Culpeper, Clarke and Stafford counties in Virginia.[9] Several other EF0 and EF1 tornadoes formed throughout the Great Plains region.[10][11]

June 5, 2008 1300 UTC Day 1 Convective Outlook

A strong jet stream moved northeast across the Great Plains region and a strong surface low in western Kansas strengthened as it moved to the Nebraska-South Dakota border. Ahead of the low, very warm and moist air spread throughout the South Central United States into Nebraska, eastern sections of South Dakota and the upper Mississippi Valley. The combination of strong winds and warm and moist air created conditions favorable for strong thunderstorms.[12] On June 5, a high risk of severe weather was issued for six different states in the Midwestern United States, with a moderate risk area surrounding the high risk area.[13] Forecasters had warned of a potentially historic outbreak, as computer forecasting models for June 5 resembled those on June 8, 1974, when 39 tornadoes struck the southern Great Plains and killed 22 people. Wichita State University canceled evening classes because of the weather predictions.[14] Severe weather began developing across eastern Colorado and northwestern Kansas during the morning and into the early afternoon, producing several weak tornadoes in the process.[15] An EF1 tornado impacted a campground near Kellogg, Iowa and injured two people. Despite extremely favorable conditions, severe weather for the day was limited and the tornadoes generally caused minimal damage.[16]

Damage caused by the EF3 Emmaville, Minnesota tornado on June 6

During the morning hours of June 6, two strong tornadoes caused damage throughout Wadena and Hubbard counties in Minnesota. The first tornado, rated EF2 on the Enhanced Fujita Scale, touched down south of Stocking Lake and downed several trees onto cabins, vehicles and storage sheds. It also toppled an irrigation system in a field north of the lake. The tornado moved to the north and expanded to its maximum width of 450 yards (410 m) and reached estimated peak winds of 130 miles per hour (210 km/h). Eight turkey barns were destroyed, killing an estimated 15 to 20 thousand turkeys. The tornado swept a home north of the area in Hubbard County off its foundation, as well as causing damage to several homes along with hundreds of acres of forest.[17] One man working at a turkey barn was injured.[18] The storm then produced an EF3 tornado, which eventually grew to a width of 400 yards (370 m) and reached wind speeds of 160 miles per hour (260 km/h). At Pickerel Lake, it nearly flattened every tree in the area, while destroying a trailer home, a camper, a garage and a house. At northern sections of Pickerel Lake, one home had its roof torn off and numerous trees were snapped onto other residences and farm buildings. The tornado began to lose its intensity but continued to topple trees, damage storage structures and toss debris before dissipating in Emmaville.[17]

A series of impulses moved from the central Rocky Mountains into the central Great Plains. Opulent moisture formed over the Missouri and Mississippi Valleys with dew points reaching near 70 °F (21 °C). Strong low level winds over the area created favorable wind shear for supercells.[19] During the afternoon, a supercell developed in western portions of Illinois and moved northeast reaching Lake Michigan around the Illinois-Indiana border in the Chicago metropolitan area, during which it produced eight tornadoes along its path.[20] At 4:21 pm (2121 UTC), an EF0 tornado occurred 4 miles (6.4 km) east of Cornell in Livingston County. The tornado occurred in an open field with no damage observed. At 4:31 pm CDT (2131 UTC), an EF1 tornado touched down southwest of Dwight in Livingston County, snapping power poles and damaging trees and roofs; this tornado lifted at 4:45 pm CDT (2145 UTC). From 5:18 pm CDT (2218 UTC) to 5:46 pm CDT (2246 UTC), an EF2 tornado traveled 13.6 miles (21.9 km) across southwestern Will County and extreme northwestern Kankakee County, near Wilmington, uprooting trees, damaging homes and destroying sheds. At 5:51 pm CDT (2251 UTC), an EF2 tornado touched down for three minutes in central Will County near Wilton Center, destroying a garage and severely damaging a metal building. From 5:55 pm CDT (2255 UTC) to 6:08 pm CDT (2308 UTC), an EF2 tornado occurred west of Monee, leveling barns, garages, and outbuildings and damaging homes. An EF2 tornado re-formed at 6:13 pm CDT (2313 UTC), injuring six people as it crossed Interstate 57.[21]

Southwest portions of Omaha, Nebraska sustained significant damage from an early-morning tornado on June 8

As the tornado moved into more densely populated southern Cook County, it destroyed homes in Richton Park. The tornado then skirted through Park Forest uprooting trees, before dissipating near Olympia Fields and Chicago Heights at 6:30 pm CDT (2330 UTC). This was the strongest tornado to strike Cook County since the March 1991 Lemont tornado. At approximately 6:32 pm CDT (2332 UTC), an EF1 tornado hit Chicago Heights, causing minor damage to several homes, with two homes sustaining significant damage. At 6:49 pm CDT (2349 UTC), an EF0 tornado touched down in Lansing, damaging tree limbs.[21] In Wisconsin, five people suffered minor injuries after an EF2 tornado went through Columbia County.[22] Further west, a new complex of storms produced two tornadoes inside the Omaha metropolitan area during the early hours of June 8.[23] A total of 539 homeowners reported damage from the tornadoes. Seven homes were destroyed and 21 others sustained major damage.[24] The two tornadoes that hit the region were rated EF1 and EF2.[23] The EF2 tornado was the strongest to strike the Omaha metropolitan area since 1975.[25]

Velocity scan of the Little Sioux tornado at the time it hit the boy scout ranch

A storm system moved to the northern and central Great Plains region during the day, as strong winds helped push a moist air mass northward ahead of the system. Thunderstorms developed during the afternoon ahead of a cold front from southeast South Dakota into central Kansas. Strong winds along with instability in the atmosphere created favorable conditions for supercell development with the potential to produce strong tornadoes.[26] At approximately 6:35 pm CDT (2335 UTC)[27] a tornado hit the Little Sioux Scout Ranch in Little Sioux, Iowa, killing four Boy Scouts after a chimney collapsed on them[28] and injuring 48 others.[29] The camp received a tornado warning 12 minutes before it struck.[27] There were 93 campers and 25 staff members at the camp. The campers were between 13 and 18 years old and were attending a leadership training camp. The tornado was rated EF3 on the Enhanced Fujita Scale.[29]

Heavy tornado damage in Chapman, Kansas on June 11

Tornadoes also caused major damage in Kansas. In Chapman, one person was killed and three others were critically injured[30] after an EF3 tornado struck the town. About 80 percent of Chapman suffered serious damage,[31] with minor damage occurring to the downtown area.[32] 70 homes in Chapman were destroyed with 215 receiving damage. Two churches were demolished and the town's elementary, middle and high schools were severely damaged.[33] Manhattan was also heavily impacted by a tornado that was rated EF4 on the Enhanced Fujita Scale. Forty-five residences in Manhattan were destroyed, as well as two mobile homes and three businesses. An additional 67 residences, three multi-family homes, one mobile home and 10 businesses suffered significant damage. Also, 75 single-family residences, three multi-family structures and 20 businesses sustained minor damage, and 637 residences, 93 multi-family structures, 20 mobile homes and 10 businesses were partially affected. An elementary school was also heavily damaged in Manhattan.[34] There was also damage to Kansas State University, where the Wind Erosion Lab was damaged. Also suffering severe damage was the engineering complex, the Sigma Alpha Epsilon fraternity house, Waters, Call and Cardwell halls as well as Ward Hall, which houses the university's nuclear reactor.[35][36] One person was also killed near the town of Soldier in Jackson County from an EF2 tornado.[33] 32 homes were damaged in Jackson County.[37] The southern outskirts of Salina near the junction of Interstate 135 was also hard hit by an EF3 tornado. Several homes, outbuildings, trees and power lines were damaged in the area.[38]

Early June rainfall estimates over the Central U.S.

The same series of systems contributed to a significant flooding event in many parts of the Midwest. Several counties in this region in Iowa, Illinois and Wisconsin were declared disaster areas. Over 10 inches (25 cm) fell in areas over the course of a week, and in Indiana some rivers approached levels similar to flooding in 1913 which killed 200 people.[61] In Franklin, Indiana, water at one point reached the first level of the area hospital, and buildings at Franklin College were damaged. Flooding was reported also in Columbus, Helmsburg and Terre Haute, Indiana. US Coast Guard units were deployed in assistance for rescue efforts. Parts of Interstate 65 and U.S. Route 31 were temporarily shut down. Thirty thousand people in Indiana lost power during the storms, and several counties filed disaster declarations.[62]

Extensive flooding near Seymour, Indiana (NWS Indianapolis)

Beginning on June 8, flooding also started occurring across parts of Iowa following several round of thunderstorms and heavy rains. In Parkersburg, Iowa, a levee burst, flooding three nearby highways. In New Hartford, which was also hit by the same tornado, water gushed over a levee forcing the evacuation of 650 people.[63] The flood waters also damaged a water treatment plant leaving Mason City without drinking water. Up to 5 inches (13 cm) of rain fell in parts of the state.[64] Mandatory evacuations were also made in Cedar Falls and Waterloo.[65] Several entire blocks in Cedar Rapids were under water (which was at times as high as stop signs) after the Cedar River overflowed its banks.[66] Flooding later affected the Iowa City area along the Iowa River where 20 buildings on the University of Iowa campus were affected.[67] Many other towns across the state became flooded as well as the rising water levels slowly made their way into the Mississippi River across southeastern Iowa, western Illinois and northeastern Missouri.[68]

Flooding was also reported north of Mason City in southeastern Minnesota, where several inches of rain closed roads and forced evacuations. Gays Mills, Wisconsin was evacuated for the second time in ten months when the Kickapoo River flooded the town. These same areas were also affected by the 2007 Midwest flooding.[69][70] From June 3 to June 11 eight people were killed due to flooding; three in Indiana,[71] three in Michigan,[49] and one in Illinois and Minnesota.[72][73]