Dexter is an 11-year-old boy living a comfortable suburban life in Joplin, Missouri. He possesses a strong fascination with tornadoes and natural disasters, frequently watching television shows about extreme weather. Though he worries constantly about his older brother deployed overseas with the military, he is adventurous and eager to learn about storm chasing firsthand. He rides his bicycle through his neighborhood with his dog at his heels, maintaining friendly ties with the local community.

Dr. Gage is a well-known storm chaser and the host of the television show Tornado Mysteries. He is an old college friend of Dexter's father visiting town for a workshop. Driven by a childhood encounter with a deadly tornado in 1974 Alabama, he now dedicates his life to researching storm prediction methods. He operates a specially equipped SUV featuring radar screens, safety gear, and deployable sound pods used to study atmospheric pressure.

Jeremy is Dexter's 20-year-old older brother and his closest confidant. He is a United States Navy SEAL whose dangerous career causes his family constant worry, despite the neighborhood viewing him as a local hero. He values routine and discipline, having taught Dexter the importance of making a bed perfectly to ensure a good start to the day.

Zeke is Dexter's loyal and protective pet dog. He is highly attuned to his surroundings and to Dexter's physical safety. When Dexter becomes distracted by thoughts of his brother and rolls through a stop sign, Zeke physically intervenes by pushing the boy off his bicycle to save him from an oncoming SUV.

David is Dexter's father and a math teacher at the local high school. He has deep roots in the Joplin community and trusts his old college roommate's expertise when it comes to extreme weather. He advocates for Dexter to experience the storm chase, believing it to be a unique educational opportunity.

Deb is Dexter's mother, who also works as a math teacher at the local high school. She values family traditions, particularly Saturday night Scrabble games, and is understandably protective of her children. She eventually relents to let Dexter go on the storm chase after receiving reassurances from her husband.

Jimmy is a storm chaser who tracks dangerous supercells across the Midwest. He walks with a severe leg injury sustained while chasing an unpredictable EF-5 tornado in the past, serving as a living reminder of the extreme dangers associated with studying volatile weather.

Sara is a fellow storm chaser who travels in a pickup truck tracking volatile weather patterns. She works closely with other chasers in the community to monitor developing supercells and share critical field information.

Dylan is a boy in Dexter's neighborhood and his former best friend. He has recently found a new group of friends but remains highly interested in hearing stories about Dexter's older brother in the military.

Mr. Tucker is a neighbor of the James family who grew up alongside Dexter's parents. He is friendly, community-minded, and takes an active interest in checking up on Dexter's military brother before leaving for a family trip to Arkansas.

Stephanie is one of the twin daughters living in Dexter's neighborhood. She runs a lemonade stand with her sister on the weekend, demonstrating the quiet, safe nature of the Joplin community before the storm.

Bobbie is the twin sister of Stephanie, living in the tight-knit Joplin neighborhood. She spends her weekend mornings selling lemonade to neighbors passing by before packing up for a family trip.