He walked the crash site before noon Sunday, trying to envision how his son's speeding car went airborne three times and crashed through a concrete-block wall.
Jeremiah Grady Simpson of Tampa, who turned 28 this month, died in that one-car crash early Sunday in Mulberry, south of Lakeland in Polk County.
"We're trying our best to try to find out what happened," Stephen Simpson, Jeremiah's father, said Sunday. "We don't have any idea why he was going south of Mulberry. No idea. Not at 2 in the morning."
According to the Polk County Sheriff's Office, Jeremiah Simpson was driving a Volvo C30 south on Church Avenue near State Road 60 about 1:40 a.m.
After passing over a dip in the road, the car went airborne for the first time, returning to the roadway where it bottomed out, gouging part of the road surface.
Simpson appears to have lost control of the Volvo at that point, with the car turning sideways and striking a curb on the west side of Church Avenue, according to the Sheriff's Office. The car continued south, crossing over a set of railroad tracks and then a road in front of Master Containers Inc. at 209 Phosphate Blvd.
The Volvo, still sideways, struck a second set of railroad tracks and went airborne for the second time, clearing SW Second Street without touching the road. It came down in the grassy lot next to a commercial building at 307 S Church Ave., described by deputies as a maintenance building for Corrosion Control Inc.
Leaving the ground for the final time, the car struck the side of the building, crashing through its concrete-block wall and landing upside-down inside the building. The impact left an approximately 15-by-25-foot hole.
Simpson died at the scene.
Shortly after 10 a.m., Stephen Simpson walked the path of debris carved by his son's careening car. Along with his brother, Lonnie, their father and a family friend, he collected tokens of his son, a former Army specialist and reservist in the National Guard.
Here, his warrior's manual, left over from his training days. There, his prized Ray-Ban sunglasses, still in their case. Further down, a multi-use tool he often carried with him, especially on the golf course.
Simpson had recently moved to Tampa after living with his parents in Lakeland, where he grew up. He attended the University of Florida and was a zealous Florida Gators fan.
The last his family heard from him was a post on Facebook, lamenting the loss Saturday to the South Carolina Gamecocks, Lonnie Simpson, his uncle, said.
He was close with his family, especially his grandparents who moved to Mulberry to spend more time with him, his uncle said. After his grandmother died last year, he would often stop by his grandfather's house for an impromptu visit.
"He was living life," his uncle said. "He's one of those people that we can learn a lot from because he took life as it was."
Simpson grew up fishing, hunting and exploring the outdoors with his father. The two would go on trips across Florida and sometimes out of state. As he got older, they also played golf together.
"He literally lived for sports," his dad said. "That was his thing. He was going do something in sports management."
Family members described Simpson as quiet and reserved. They called him a clever, perceptive man with an infectious laugh.
Simpson spent Saturday night watching the Gators game with friends at the Socialite, a bar in Lakeland, his dad said. His family is still unsure what led to the violent chain of events that caused his car to crash into the side of the building in Mulberry.
The Sheriff's Office says excessive speed likely contributed, and deputies will seek to determine whether Simpson was impaired.
Times staff writer Bill Varian contributed to this report.