Continuity mistake: During the big falling debris scene, Paxton and Helen Hunt are in the red truck. The truck hits a tractor. The impact damages the windshield, and it is clearly broken, but a second later the windshield is perfect and untouched.
Continuity mistake: When the cow blows by the truck, the truck is driving down an empty dirt road with water on both sides. During the shots of the occupants, the road behind the truck is paved, and in one of these rear shots a truck drives by in the opposite direction.
Factual error: In the begining when Jo's dad is bringing the family downstairs and say's "TV says it's big, might be an F-5" That scene was set in 1969. In reality he would not have known anything about an F-5 or any tornado with an F rating because the Fujita scale was not developed until 1971.
Continuity mistake: When the telephone pole falls on the truck, you see Dorothy get thrown off the bed and the tailgate gets broken off along with it. A couple of scenes later, the tailgate is back and hanging there like it was untouched, and the pole is no longer there.
Continuity mistake: When Bill and Jo are going through the house, the house is on its side horizontally. When they are crashing through the rooms though, the rooms are vertical. Also, in the same scene, you can clearly see them going up the stairs to the second floor. When they burst out, they are magically back down on the first floor. Right after that, the windshield is all cracked. A second later, it's perfectly fine.
Continuity mistake: When the solid water funnel comes and Bill, Joe, and Melissa are chasing it, if you look from when they are not up to the dirt road, surrounded by water, to when they almost get blown away, there is a red car driving by.
Continuity mistake: After Bill Paxton and Helen Hunt chase the first tornado they switch to Bill's new truck. They look at the speedometer once then they look at again about 3 seconds later and the odometer is hundreds of miles different than it was only 3 seconds before.
Other mistake: Although the film is set in Oklahoma (and north of Oklahoma City), the roads are marked by Texas road signs.
Visible crew/equipment: Near the beginning of the movie when Bill and Mellisa are on their way to get the divorce papers signed, you can see the reflection on the passenger side window of the helicopter and the cameraman. A few shots later when the camera angle is in front of the Dodge, you can see a brief reflection of the brake lights from the camera truck in the rear window of the Dodge.
Continuity mistake: After leaving Aunt Meg's the first time, Jo and Bill are in the red truck. Bill says, "Ok, let's get you wired." When Jo looks over at him you can see that she already has the headphones around her neck. Then they cut to Bill and when he goes to put the headphones on her neck is bare.
Continuity mistake: After the last tornado that passes directly over them, of F5 intensity, immediately afterwards, Helen Hunt still has her lightweight headphones casually draped around her neck. A stiff breeze could have blown them off, but not an F5 tornado?
Continuity mistake: When the good group is chasing the tornado, the bad group is following them (watching for skid marks on turns, etc.) anyway, the bad guys see skid marks at a turn about 10ft in front of them. They would have to turn immediately and they would still barely make the turn. The camera goes off the road and shows the driver's "what do I do??" expression for about 3 seconds, then the camera goes back on the road and the turn is the same distance away. In reality they would have passed the turn and been about 20 ft past it by then.
Plot hole: Throughout the entire movie, barns, houses, cars, 18-wheelers, etc. are demolished and lifted into the air like they were made of paper. And yet Jo and Bill pass through one tornado after another with nothing more than their hair getting messed up (a little.) You'd think just the debris flying into their faces at 100 miles an hour would be enough to give them a few injuries.
Visible crew/equipment: When they are trapped in the garage and the tornado is whipping through, if you look real close when the debris is falling on them you can see (very quickly) a crew member throwing trash in the background.
Revealing mistake: They wouldn't be able to walk or run nearly so easily when near a tornado. In ametuer video footage of real tornados, the people could only move quite slowly, and were walking on an angle of 30 degrees from upright.
Continuity mistake: When Jo's crew is having their little steak snack at Aunt Meg's, we see Preacher watching TV. There's a good shot of the top of the television set and there are NO walkie-talkies on top. Yet when they hear about another tornado, they all jumped up and grab their walkie-talkies off the top of the TV.
Visible crew/equipment: There's a shot late in the movie at Helen Hunt's Aunt's house - the camera shows all of her home made "wind chimes" blowing in the wind. As the camera pans in and shows a little man sawing or axing something, you see a human hand appear near the bottom of the screen as the camera leaves the scene.
Other mistake: When the Tree gets blown under the red truck and they get stuck on it. Why don't they ever put the truck in 4WD? You can see the front differential and 4x4 markings so the truck definately HAS 4WD. That particular year of truck doesn't even require you to get out and lock the hubs.
Continuity mistake: When they are at the drive-in movie "The Shining" is showing just as he sees the two girls, but five minutes later the guy is knocking down the door with an axe, these two scenes occur an hour apart.
Continuity mistake: Towards the beginning of the movie when Melissa goes on the first chase, she is under an umbrella with her hair dry. They cut away go back, she is drenched, cut away go back she is soaked, go back again, she is wet.