Eighty one separate twisters were reported across the Midwest. The devastating storm outbreak brought winds of up to 200mph that flattened hundreds of homes and killed six people.
Residents of Washington, a downstate town of 15,000, were left to pick up the pieces Monday and begin recovering from the disaster.
Bits of American flags and insulation from destroyed houses clung to trees that had been stripped of most of their branches and remaining leaves by the twister.
Police were keeping residents from returning to the storm-hit area, where buildings were destroyed and cars turned upside down, out of concern that people could be injured while attempting to retrieve possessions.
Ryan Bowers, 33, and his wife Andrea, 32, briefly returned to retrieve a family Bible and pink baby rattle that was their 2-1/2-year-old daughter Sydney's favorite toy.
'We're back here just to get any idea of what everything looks like,' Ryan Bowers said. 'We have what's important. My wife and daughter are OK. That's all I can ask for.'
As they picked through the wreckage of their home, a police officer approached and told them they had to leave.
Mayor Gary Manier said authorities were keeping evacuated residents away out of concern that the remaining structures were dangerously unstable.
'I know it's frustrating for people,' Manier said amid piles of rubble. 'I'd be frustrated. I'd want to be looking for pictures.'
Manier estimated that 250 to 500 homes had been destroyed by the tornado, rated as the second-most powerful magnitude of twister, which hit the city east of Peoria with winds of 166 to 200 miles per hour.
The storm killed three people in Massac Country, two in Washington County and one in the city of Washington, in Tazewell County, said Patti Thompson of the Illinois Emergency Management Agency.
Illinois State Police spokesman Dustin Pierce said about 120 people were injured in Washington.
Survivors of the storm said they rode it out in their basements, which are common in homes in the affected area, a fact that may have helped hold down the death toll, officials said. In May, a monster, top-category tornado killed 24 people in Moore, Oklahoma, a part of the United States where basements are less common.
Nancy Rampy, 62, said she fled to her basement when she heard the storm sirens blaring on Sunday.
'It got real calm and I knew that was bad because I've been in a tornado before. And then I heard what sounded like 12 trains, just roaring down the tracks, and it just wouldn't stop. It just kept coming and coming,' Rampy said. 'I ran to the basement, sat in the basement with my flashlight in the dark and just prayed let it be over soon.'
Rampy's house was spared.
Two people, an 80-year-old man and his 78-year-old sister, were killed in Washington County, Illinois, about 200 miles south of Peoria, county Coroner Mark Styninger said.
Three others were killed in Massac County, Illinois, on the Kentucky border, where a tornado devastated several neighborhoods, emergency officials said.
The American Red Cross has worked with emergency management officials to set up shelters and provide assistance.
'We literally dodged a bullet,' he said. 'When you look across the river (into Illinois), there are places that are just wiped out. But we're in good shape.'
The unusual late-season storms moved dangerously fast, tracking east at 60 miles per hour, with the bulk of the damage spanning about five hours, Thompson said. Remnants of the storm sent rain and wind to the northeastern United States on Monday morning.
The storm knocked down power lines across the Midwest and power companies reported that some 786,600 homes and businesses were without electricity on Monday. Michigan had the largest number of outages, with Illinois, Indiana, Ohio, Missouri, West Virginia and Pennsylvania also feeling the storm's aftermath.
Just as Al said.