Continuity mistake: When on the plane and there's the major turbulence Sam's hair flops over his forehead.Then he looks at the wing and there is no hair on his forehead but in the next shot of him his hair is back messed up. (00:17:55)
Continuity mistake: When Lucy is saying good bye and hugging her co-worker, she puts her arm over the co-worker's shoulder. When it cuts, Lucy's arm is gone and when it cuts it's back over her shoulder. (01:13:15)
Continuity mistake: As the tidal wave is heading towards the library, the homeless man picks up his dog and runs towards the library. In the next shot his dog is still on the ground.
Continuity mistake: When we get to the public library the first time there is a shot from behind the homeless guy - he has his hand on a cart. When it cuts to a front shot his hand is off the cart. (00:44:25)
Continuity mistake: When T.J. is talking with the homeless black guy who is sitting on the floor telling the student how to keep warm, the guy throws the student a book to rip up and make himself warm. When he throws the book, the student is grasping the book at the bottom with his left hand, but in the following shot his left hand is at the top of the book. (01:16:30)
Continuity mistake: When Sam is sitting in the kitchen eating, his mother is talking to Jack on the phone and just after Jack says, "Sam is a straight A student he doesn't fail classes," Sam puts down his glass of milk and leaves his left hand up, but in the following shot it is down by his stomach. (00:12:25)
Continuity mistake: The image from the space station that is sent to Tamlyn has no vortex. However when she sees the images on her screen there is a vortex about 50 miles in diameter.
Revealing mistake: During the tornado scene there is a part where you see lots of cars on the highway flying and crashing and if you look carefully at the second car falling it doesn't touch the ground, yet it manages to cause sparks and dents.
Continuity mistake: When the man asks Jack "Why for the love of God would you aggravate the Vice President?", he has both his hands up. When it cuts his hands are down. (00:13:20)
Factual error: When we see a TV report saying how England is affected by the storm we see a shot of a street with hanging yellow traffic lights. England doesn't have yellow traffic lights, we have black ones. It's obviously footage of a storm in the United States.
Revealing mistake: In the scene where Dennis Quaid jumps over the ice crevasse to the other side, note the position of his ice axe, which is strapped to the right side of his hip. When he jumps back over with the metal tubes in his hands, he balances a little, then falls. We see his gloved hands disappear as he falls into the crevasse. The next shot shows he is holding onto the ice axe, which is embedded into the ice with his left hand. In reality he would not be able to unhook the ice axe so quickly and then put it in his left hand and thrust it into the ice. Remember what gravity does.
Factual error: Football matches shown on TV are never cut well into the 2nd half to be "welcomed back" at 63 mins. And no British commentator would say "Glasgow, Scotland"? In the UK we know Glasgow is in Scotland. He would say the stadium name - Celtic Park.
Other mistake: At the end of the movie, when they pan out to show the ice cover on the Earth reaching down almost to Mexico. Look closely. The Great Lakes are not frozen.
Factual error: When some people are burning books in the library, one man is adamantly protecting a Gutenberg Bible. Considering how rare and valuable Gutenberg Bibles are, it would not have been on the shelf or even readily accessible. Likely it would be locked in a safe or at least a showcase. Considering the shortage of time to collect fuel and the plethora of books available, I doubt they would break into a locked container to get another bit of fuel.
Suggested correction: According to Wikipedia, and other online sources, the Gutenberg Bible of the New York Public Library is publicly on display. It's shown in as being in a glass display case, there for anyone to see. There's no evidence that the book was taken for fuel. The first we see of it, it's being held by the person safeguarding it. It's possible they took it specifically to keep it safe. https://en.m.wikipedia.org/wiki/Gutenberg_Bible.
Suggested correction: He was the head librarian, and as such would have access to the safe/showcase. And he would want to keep the Gutenberg as close as possible to protect it.
That man clutching the Gutenberg was NOT a librarian, much less a "head librarian." He was just one of the civilians who came into the library to escape the climate onslaught. He wouldn't have access to something as precious and priceless as the Gutenberg. Original flaw remains valid.
Continuity mistake: When the students are looking around the library for books to burn, it cuts to a girl and man standing on the balcony beside a book cart. When the guy reaches across to grab a book and says, "We can't burn this one..." he is holding the book with both hands, but in the following shot his left hand is on the book and the other hand is on the cart. (01:11:35)
Continuity mistake: In the scene where Sam smashes the vending machine in the library, you see him first take out about three items from it, and then in the next shot you see him holding two items, but when he throws them onto the table there are about a dozen packets of sweets and crisps. (01:11:25)
Factual error: When the students arrive in New York, you can see the luggage tag on Laura's bag. It lists JFK below DCA. This means the bag would have flown from somewhere to John F. Kennedy airport in New York, and then connected onto another flight going to Reagan National in Washington DC. Since New York is their final destination, JFK should have been the top airport code, even if they had connected through somewhere else.
Continuity mistake: Just after Terry looks at the boys on the screen with Simon, in the overhead shot of Manhattan traffic, the homeless guy in the middle of the traffic is walking towards a black car with a police car beside it. But in the following closeup he has passed the cop car and is now at the bumper of the black car. (Zoom in is required). (00:19:00)
Continuity mistake: When the tidal wave is about to hit Manhattan, Sam and his two friends are walking up the stairs, and the black friend's hood is over his head, but in the following shot it is no longer over his head. (00:46:35)
Continuity mistake: The older scientist reaches down to grab Jack with his right hand. In a closeup, Jack grabs the right hand and the same scientist catches him with the left hand as well. In the next shot from above, only his left hand is down, but as he pulls Jack up both hands are on him. (00:05:40)
