Yes, the screen tear. I always assumed it was a brand name or something, maybe the type of screen, because it was just called the Barco Screen and the effect was the barco tear. Never found out the why, was just told what it was called and what it was supposed to do. That is a terrible terrible answer to your question, I'm sorry!
Oh, let's see, the sign in question would have been to your left entering Scene 2 from Scene 1, on the wall next to the hallway that leads to the TD booth. I can't remember if it was a warning sign for the attraction, or a fake news article. You'd never see it as a park guest, it's too dark and loud and the TM's are hustling you inside. But when you're frozen in Scene 2, standing by the doors waiting for them to open, you do a lot of pacing around and a lot of looking at the same stuff over and over again. That is how I discovered... the mighty tornmado typo.