Visible crew/equipment: When Bill Paxton and Helen Hunt are driving up to Aunt Meg's house after the tornado has hit, you see a shot of the ruined home as they drive up. If you look carefully, you can see wires hanging coming out from the top of the house to keep it from collapsing until the filmmakers were ready.
Other mistake: During the garage scene, we see a large neon sign get ripped off of its mounting pole and thrown into the garage. It seems obvious that the sign is no longer connected to any sort of electricity source, however, the sign stays lit as it is ripped off its pole, into the next shot when it crashes into the garage, and then it continues to flicker a bit as it lays on the ground.
Visible crew/equipment: After leaving Wakita, Bill and Jo are driving through a cornfield. The cornfield merges into the main road and their truck almost runs into Jonas' fleet. As the truck enters the road, you can see a crew member poking his head up from the corn across the road. Watch above the driver's side mirror.
Factual error: In the last scenes when Bill and Jo are in the shed with the water pipes, the shed is torn apart by wind as well as flying debris at hundreds of miles per hour. I have watched the scene numerous times and there is not so much as a scratch on their faces. Even if they lived, they would have been battered and bloody from debris. Regardless if tornadoes do weird things, the debris ripped the shed apart, which is stronger than a human body.
Other mistake: In the scene in the garage pit, one of the characters is hit in the forehead by a flying hubcap. He is cut clear across his forehead, but there is only a small trickle of blood oozing from the wound. I've seen many scalp lacerations and even the most minor ones will bleed like a stuck pig, where's all of that blood?
Other mistake: When the twister hits the drive in theater, the sirens are wailing, but nobody reacts. Only when Jo screams at the waitresses they start panicking and run. The movie is set in Oklahoma, smack in the middle of tornado alley. The people there know what the sirens mean, they sure don't need no out-of-town big-shots to tell them to get under cover.Doc
Continuity mistake: When Bill and Melissa go out to get the divorce papers from Jo, we see Bill pull his truck up with Rabbit and Allan's truck (hood up) in the background. We see it closer up when Bill asks Dusty, "Where's Jo?" But when the scene comes back to Bill and Dusty and then shows Melissa, Rabbit, Allan and the truck have disappeared. When Dusty is holding Melissa's hand and walking to sit in his chairs, Rabbit & co. are in the background again.Sheri Hartman
Continuity mistake: When Bill and Jo are strapped to the water pipes in the final twister scene, after the tornado passes and they are back on the ground, one of their leather straps are already broken. In this condition it never would have held itself on that pipe, let alone an average sized human being.