Character mistake: The Captain of the USS Fragasso comes onto the bridge. A Petty Officer says, "Officer on deck," and salutes while looking out the forward windscreen. He should have said, "Captain on the bridge" and not saluted.
Other mistake: In the Special Thanks section, Bobcat Goldthwait's name is misspelled as "Goldthwaite." (02:28:28)
Continuity mistake: Scott hugs his daughter and caresses her face while she holds his wrist. From the opposite angle, her hand is gone.
Continuity mistake: When Coriolanus and Sejanus are eating lunch at the Academy, Coriolanus' sandwiches switch positions several times, stacking and unstacking, and turning several times.
Continuity mistake: Towards the end of the movie, Kamala asks Carol on the porch, "Hey, do you still fly that thing?" She is holding her right hand with her left. The camera angle switches, and her left hand is low, out of frame and comes back up only seconds later after Carol's answer.
Continuity mistake: Before Francois writes on the whiteboard (dry-erase), the words at the top are not boxed-in (or underlined). After being boxed-in, the words are surrounded by more of an oval shape, then not highlighted at all - but the words on the third line are boxed-in, followed by being underlined 4 times, to not underlined, to being boxed-in again. (00:17:28 - 00:19:05)
Visible crew/equipment: As Doric leaves the house after transforming from a cat, a crew member can be seen in the background. The crew member is casually leaning against a wall, with a red T-shirt and a face mask. (00:41:18)
Suggested correction: This person is a tiny figure on the extreme right of the screen who is on screen for a fraction of a second while the camera is panning away from him. I had to watch the scene multiple times before I saw what you are referring to. Even then, he is only identifiable if you freeze-frame the picture, thus invalidating the mistake. (At normal speed, I initially thought he was a red banner or curtain).
Factual error: The storm chasers are meeting by the road and you see the sign for I-90 East in the background several times. This movie takes place in and around Texas, yet the route that I-90 takes is nowhere remotely close to that far south.
Factual error: Professor Alessando steals the keys from the ward. One key is under a copy of the Italian magazine "L'Eternauta." However, it is issue #103, released in November 1991. The movie is set one year earlier, at the end of 1990.