As the storms moved into Missouri later that night and into the early morning hours of February 29, numerous strong tornadoes touched down.

[4] As the storms moved into Illinois in the pre-dawn hours, they merged into an intense squall line with embedded semi-discrete supercell thunderstorms.

A violent EF4 tornado touched down and ripped through the city of Harrisburg, destroying entire neighborhoods, flattening businesses, and killing 8 people before causing additional destruction in the neighboring town of Ridgway.

The Harrisburg/Ridgway tornado was spawned by a semi-discrete supercell thunderstorm embedded within a larger squall line of storms that was racing through southern Illinois at the time.

[8] The tornado continued to intensify as it entered the southwestern edge of the city at 4:56 a.m., tearing through the Dorrisville neighborhood at EF2 strength, where many homes sustained significant damage and numerous trees were snapped and uprooted.

The tornado then rapidly intensified into a violent EF4 as it crossed South Commercial Street, where some businesses were completely leveled with only piles of rubble left behind.

Several other businesses were damaged, and the large Christ Lutheran Church was flattened with debris wind-rowed long distances through a nearby field.

[16] Westboro Baptist Church commented on the event, which prompted locals to create a "shield of support" around the funeral processions with thousands attending, standing in large groups around the city.

[18] The tornado damage in Harrisburg dominated national airwaves for several days with both Anderson Cooper, and Diane Sawyer doing special reports.

[19][20] Both The New York Times and Chicago Tribune wrote articles on the resilient history and nature of Harrisburg in the wake of the tornado and floods that have hit the city since its founding in 1889.

The tornado continued through very sparsely populated areas of Saline County, traversing open farm fields and debarking several additional hardwood trees at EF3 strength.

As the tornado passed to the south of Eldorado, trees were uprooted and another house had significant roof and exterior wall loss, with the damage at that location rated high-end EF2.

A factory building was severely damaged, many large trees were snapped and uprooted, power lines were downed, and about a half dozen grain bins were completely destroyed.