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. (00:02:45)
Revealing mistake: At the start, while Jo and her parents are inside their storm cellar, Jo's father attempts to hold down the overhead cellar door during the tornado. Then, just as the F5 yanks the cellar door up along with Mr. Thornton, we can see the cable link that is attached between the actor's back and the cellar door, for this stunt. (00:04:20)
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. (00:07:50)
Continuity mistake: When Bill is going over the divorce papers, he comes to the page missing Jo's signature. It only has one red arrow near top right. When he hands it to Jo, she starts looking at it, then flips up page to look at others, and the missing signature page is a completely different page with two red arrows, one toward the top and another, on the right, toward the bottom. (00:12:25)
Continuity mistake: Near the beginning, when Bill and Melissa have gone to get the divorce papers, Bill leaves Melissa talking to Dusty. When Dusty starts telling her about the "suck zone" there are a couple of black cows behind Dusty. Next, Jo comes over to meet Melissa and when the camera pans to the same area behind Dusty, there are no cows. (00:12:50)
Audio problem: When the two storm chasing crews have stopped at the Hot Pit Bar-B-Q, in the shot where Bill runs over to beat up Jonas for supposedly stealing his design for Dorothy, Jonas's mouth is not moving and yet we hear him continuing to talk about DOT 3. (00:19:45)
Continuity mistake: At the roadside restaurant, when Bill first sees Jonas' version of Dorothy, we see it from Bill's perspective. You can see that the panels in DOT's top are open. In the next shot, Jonas is discussing DOT with the press and the top is closed then opens as he describes the sensors. (00:20:25)
Continuity mistake: When they make their pit stop at the BBQ diner Bill is outside with Dusty and says, "we're going green". The sky is dark and green. When Jo comes out and they're ready to go a few minutes later, the sky is almost sunny and it's suddenly partly cloudy. (00:25:10)
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. (00:31:10)
Visible crew/equipment: When Melissa dodges the truck that has fallen from sky and Dusty rushes to open a door and help Melissa get out of the truck, the reflection of a camera is seen in the bottom right corner of the truck window. As they move out and pan to the right, you can see a reflection of the same camera and cameraman at the bottom right corner of the truck door as they move away. (00:33:50)
Continuity mistake: When Jo's truck is lifted by the first tornado they encounter, it is dropped on the road in front of the red dodge driven by Bill's fiancée. When we see the truck drop, the drivers window is closed. As the dodge swerves to avoid hitting the other truck, the window is now opened. And finally, in the last shot where everyone is running to her aide, the window is closed again. (00:34:05)
Continuity mistake: When Jo's truck lands in the road, right after which Jonas' crew drives by, if you look quickly, you can see that the driver side (the truck was upside down) window is gone. Yet, when Jo goes to get her backpack out, she has to kick that window out. (00:35:25)
Continuity mistake: In the movie the antagonist Jonas has a vehicle fleet that includes the main vehicle, a Chevy truck, 4 black Dodge Grand Caravans, and a large recreational vehicle. At 37:15, a faraway camera shot shows the Chevy and 4 black minivans in a convoy, but the RV is nowhere to be seen. In the next shot, Bill, Melissa, and Jo arrive in the Red Dodge Ram, the RV is at the back of the convoy, and there are only 3 minivans between the RV and the Chevy at the front. (00:37:15 - 00:38:15)
Continuity mistake: In the scene where Bill is trying to catch up with Jonas, right after Bill stops the truck, we see a long shot of Jonas's storm chasing crew passing Bill's truck, a side road can be seen on the right side of the road. But when Bill puts the truck in reverse and turns onto the side road it's now on the left side (there never was a side road visible on the left side in the long shot). (00:38:35)
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 dry. Also in one of these rear shots a truck (Red Chevrolet Blazer) drives by in the opposite direction. (00:42:25)
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. (00:53:20)
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. (00:59:00)
Other mistake: The order of action performed to activate Dorothy 2 (jumping tornado scene) and 4 (F5 tornado scene) is reversed. Also, Bill somehow has more switches to flip. Jo pressed a button, flipped a couple switches and then told Bill Dorothy was ready, while Bill had to flip the same switches, then flip some more, then press the buttons before starting to unstrap the device from the truck. (Jo didn't have to unstrap D4 because they realised at that point it had to be anchored to something heavy because the device was too light and decided to sacrifice the truck). However it is possible that Bill actually flipped the same switches twice. We can see him flip the switches, then we have a quick close shot of Dorothy 2 then the camera goes back to Bill flipping the switches again. There is no such angle change during the part where Jo activate D4, so it's very much probable that they got two angles of Bill Paxton flipping the switches, but forgot to cut one. (00:59:15 - 01:36:00)
Continuity mistake: Towards the beginning of the movie when Melissa goes on the chase after they leave Meg's, 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. (01:00:05)
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. (01:05:45)
Answer: Based on his scenes, he seems to be a photographer for the team. He was taking pictures of Jo, showing how Dorothy worked, and was setting up a camera when Bill and Jo were going after the F5 at the end.