The song “On a Clear Day” floated down from the speakers at the Oak Lawn Roller Skating Club as 11-year-old Mary Hanley twirled and leaped across the hardwood floor in her white-leather Snyder skates.

Her mother and older sister sat on a bench a few feet away, watching the girl who, five years later, would become a national roller-skating champion.

“I was starting my routine, and I felt this unbelievable feeling of humidity, almost taking my breath away, and it was getting very, very dark and windy,” Hanley, now 62 and a dentist living in Park Ridge, says of that day half a century ago — April 21, 1967.

So she skated to a window and peered out at the McDonald’s across the street. The golden arches were vibrating.

Inside the roller rink, the lights flickered then went dark. Then, the entire building — roof, rafters, brick and all — collapsed.

The tornado that devastated Oak Lawn that day was part of a huge storm system that spawned at least 10 tornadoes and spun a path of destruction across northeast Illinois, killing 58, 33 of them in the quiet Chicago suburb. Hundreds more were injured and thousands left homeless. It remains the most devastating tornado outbreak to ever hit this part of Illinois.

To the God-fearing, the worst of it lasted just long enough to stammer out three Hail Marys.

Even today, when a tornado warning flashes across the bottom of a TV screen, the spines of many who remember that day 50 years ago stiffen, and anxious eyes turn to the sky.

CLICK TO HEAR AUDIO:  On April 21, 1967, aspiring radio broadcaster Robert Kehe stepped outside to record a thunderstorm — and ended up capturing the sound and fury of the Oak Lawn tornado.

CLICK TO SEE MAP OF THE DESTRUCTION IN OAK LAWN

***

Some of the damage from the F4 tornado that devastated Belvidere on April 21, 1967. | Rockford Register Star.

The yellow buses —16 of them — were lined up outside Belvidere High School, about 70 miles northwest of the Loop. The drivers, with the elementary and junior high students already on board, were waiting for the big kids to arrive.

Fourteen-year-year-old Robert Ellison, one of the passengers, had an inkling something was wrong. The farm boy loved weather. He read about it constantly in encyclopedias. He heard the thunder and noticed the birds had all stopped chirping. The sky had turned a dark, swamp-green.

He told the bus driver: Maybe it would be a good idea to run in to the high school office and ask if they’d heard anything about storms in the area.

“The bus driver said, ‘We’re first in line to leave. If you run in to the building, you’ll hold all the buses up,’ ” Ellison, now 64 and living in Rockford, remembers being told.

The tornado announced itself with thrashing rain and screaming winds followed by baseball-size hail that cracked the windshield on Ellison’s school bus.

He jumped from his seat and ran for the exit. The driver snatched hold of his coat, but Ellison broke free. He ran into the maelstrom, intent on finding cover at the school.

School bus destroyed by the tornado near Belvidere High School on April 21, 1967. | Boone County Historical Society

It felt like he’d stepped into a blender. “Big chunks of roof, siding, two-by-sixes were twirling around like helicopter blades,” he says.

A chunk of wood struck him, knocking him to the ground in a field near the school. A high school girl fell on top of him and tried to shield him. As they lay there, they heard the groan of crumpling metal: Two school buses were rolling toward them.

“Their roofs are getting ripped up, hoods are being torn up, motors exposed,” Ellison says.

He and the girl got up and ran as hard as they could. It wasn’t hard enough for Ellison.

“I heard the roar of metal smashing behind me,” he says. “I turned around, and there was the bus, right on my heels. Wham! It hit me and rolled over on top of me.”

***

It was about 5:30 p.m., and Detective Frank Gilbert of the Oak Lawn police department had just stepped out of the shower. He was heading out to start his overnight shift. Before leaving, he and his wife Sandra stood outside, their eyes drawn to the southwest, where the sky was a pea-soup green. Off in the distance, the sky was flecked black with debris.

“Holy s—, it looks like a tornado!” Gilbert, now retired, remembers shouting.

They raced inside and braced themselves. They were among the lucky ones: The tornado passed without damaging their home.

“I better get to work,” Gilbert told her.

Retired Oak Lawn Detective Frank Gilbert. | Max Herman / Sun-Times

He hopped in his car and got to within three blocks of the police station before being blocked by downed power lines, sparking and jumping across the road.

He ditched the car and started walking. A woman came running down her driveway toward him, screaming.

Her roof had been torn away, and Gilbert noticed her garage door wasn’t closed properly. He took a closer look and saw two feet poking out — those of the woman’s husband, who lay dead on the ground.

Some veterans likened the devastation seen in Oak Lawn to that of war-ravaged cities. | Courtesy Oak Lawn Public Library

A neighbor rushed to console the woman. Gilbert raised the garage door and covered the body with a tarp.

When he finally got to the police station, the chief grabbed him and said, “We’ve got to set up a morgue.”

***

Damage to a Suburban Transit Company bus near 95th Street and Menard Avenue in Oak Lawn. | Courtesy Oak Lawn Public Library

Mary Hanley wobbled to her feet. A nail poked out from her right shin. Her hair was full of tar paper. She looked up, seeing sky where the roller rink’s roof had been. She looked around, frantic, for her mother and sister.

“I couldn’t find anyone,” Hanley remembers. “All I heard were screams and people crying. And then I heard lots of sirens.”

Hanley figured she’d been unconscious but had no idea for how long.

Mary Hanley, now a dentist living in Park Ridge, was at the Oak Lawn Roller Skating Club when it was flattened by the April 21, 1967, Oak Lawn tornado. | Provided photo

A woman wrapped her in a blanket and led her to a bus, which took those who could walk to Christ Community Hospital. That’s where Hanley was reunited with her older sister Ellen. Both had suffered only cuts and bruises.

“Where’s Mommy?” Hanley remembers asking her sister, who didn’t know.

Later, Hanley learned that Ellen, then 16, had been pulled from beneath the rink’s collapsed beams and bricks. As she lay trapped, Ellen held the hand of a 13-year-old girl named Christine Hinds who dreamed of becoming a flight attendant. They were still holding hands when Christine’s body was pulled free.

David Nork, 14, who played guitar in a band called The Misfits, was also buried in the rink rubble. He died four days later.

It wasn’t until four hours after the tornado hit that the Hanley sisters, still at the hospital, found out about their mother, Charlotte Hanley.

“I saw my brother and my father, who came into the front of the hospital,” Mary Hanley says. “There was a policeman and my brother holding up my father. I knew at that point my mother had died.”

***

Robert Ellison, who survived being pinned under a school bus in Belvidere, spent two days in a coma after suffering numerous broken bones and wounds that required 200 stitches to his head. | Provided photo

Robert Ellison has no idea how long he was trapped under the school bus. He was unconscious and hidden from view.

All around him, children lay dead or dying. Among them were Rebecca Louise Vogelsang, 8 years old, and John E. Tate, a 6-year-old first-grader. The storm claimed the lives of 17 students and one bus driver at the high school.

A nurse was walking amid the crumpled buses. She bent down, pointed her flashlight underneath one and saw a foot.

Crews jacked up the bus and dragged Ellison out. Someone came over to tag the body.

“No, he’s alive,” the nurse said, pointing to a wound leaking a thin trickle of blood.

For six hours, Ellison’s parents had no idea what happened to him. The teen’s mother and an older brother raced to the school, checking the makeshift morgue in the gym. They went to Belvidere’s two hospitals. Finally, they got word from a Rockford radio station that the teen was in critical condition at a hospital there. An Illinois state trooper gave them an escort to the hospital.

Ellison spent two days there in a coma. He had numerous broken bones and wounds that required 200 stitches in his head, which swelled hugely.

“I got down there and looked at you — and I looked at you — and I just couldn’t figure out that that was you,” Ellison remembers an uncle saying of an early visit to see him in the hospital.

***

Retired Oak Lawn Detective Frank Gilbert pages through the book “Oak Lawn Tornado of 1967” by Kevin Korst, recounting the damage tornadoes did to his community on April 21, 1967. | Max Herman / Sun-Times

When Gilbert, the Oak Lawn cop, reached the local Veterans of Foreign Wars post that he’d chosen to set up a makeshift morgue, men were drinking at the bar.

“I don’t think a lot of them realized what had happened,” he says.

He found the post commander and told him what he needed. Soon, the bodies began to arrive.

“We put children in one area, the women in another and the men in another,” Gilbert says.

People rarely got killed in Oak Lawn, but Gilbert was used to seeing dead bodies. As a kid, he’d tagged along with his mother, a stylist who fixed up the hair of the dead at a funeral parlor.

Nothing could prepare him, though, for the teenage girl who came to the VFW looking for her father. The girl screamed. She’d spotted her dad’s body.

“It was the most blood-curdling scream,” Gilbert says. “It went right through me. She went right down on her knees, screaming, ‘Why? Why?’ ”

When Gilbert’s shift ended at 9 the next morning, he was utterly spent. He curled up and fell asleep on a bunk in an empty cell at the police station.

***

CLICK HERE TO SEE VIDEO: Photographer Kerry Joy McGehee’s father Ronald Berghuis shot footage with an 8mm home movie camera the day after the storm hit Hometown, neighboring Oak Lawn. She says he helped rescue efforts and “pulled five small children, ages 3 to 8, one of whom was in a wheelchair, out of a house.”

Two hours before the first of the three deadly tornadoes — Oak Lawn, Belvidere and Lake Zurich — touched down, the weather service teletype machines at the University of Chicago clattered out a warning about the possibility of tornadoes in central and northern Illinois and parts of Wisconsin, Indiana and Iowa.

But nothing on the weather radar revealed an actual tornado, meteorologists said in the days after the devastation. It wasn’t until 4:15 p.m. — 45 minutes after the first tornado slammed into Belvidere — that the weather service reported it had touched down: “Extensive damage and some injuries …”

Frozen in time, this clock at the Oak Lawn Community High School stopped the instant the tornado struck. This photo was taken by Gregory D. Habas.
| Courtesy Oak Lawn Public Library

Oak Lawn was luckier. It got a 25-minute warning of the approaching F-4 tornado.

Fifty years later, tornadoes still tear buildings to bits, crush buses as if they were aluminum cans and take lives. But with the advent of cell phones, social media and sophisticated satellite and radar technology, there’s typically far more advance warning so people can prepare and find safety, says National Weather Service meteorologist Mike Bardou.

“Everything is computer-driven,” Bardou says. “We get radar information continuously. We can see more layers of a storm. The data has a much higher resolution. Now, we have the ability to see the motion, how the winds are moving, how strong they are.”

Meteorologist Mike Bardou says storm forecasting is much improved since 1967. | Rich Hein~Sun-Times

Satellite technology, in its infancy 50 years ago, often allows meteorologists to identify potentially deadly weather patterns several days in advance.

But those advances make little difference if people don’t heed the warnings.

Those who survived the 1967 twisters don’t need to be reminded.

“For the first three or four years after the tornado, I was terrified every time the sky got black and they issued a tornado watch,” Ellison says. “I sat in a chair out in the garden because I had an unobstructed view to the west and southwest. I would just sit in that chair, staring at the distant sky.”

But he says his fears have waned in the passing years.

Mary Hanley’s have not.

“It has ruined my life, this tornado,” the suburban dentist says. “To this day, when it storms, I have to leave my patients and find a basement.”

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