Tom is driving home on Christmas Eve in a freezing storm, yet when they show the car radio you can see the heater controls are off and the temp lever is all the way on cold.
Backdrop image at end of film where wife and children are standing is a picture of Arizona desert filled with Saguaro Cacti when the previous and post shots are clearly made in the So. California Mojave desert with Joshua trees everywhere.
When Tom knocks on the motel door and the shot switches to show Gloria and Ernie in the room the number 18 is visible on the door, but when the shot switches out to show Tom talking to Ernie, the number is not there.
At Charlie's before the Phillips family arrives, Ernie drinks from a water fountain located near the center of the building. Seconds later, while arguing with Tom, the water fountain is all the way at the end of the building. After the Phillip's leave, when the Corvette comes flying around the corner, the fountain is in the center again.
In the final scene the officer pulls up and gets out of his patrol car wearing a helmet. Police officers don't wear helmets when driving cars.
In the garage scene, a placard can be seen showing the name of the proprietor spelled "Charlie's". In the final credits, the character is billed as "Charley".
At 1:29.06, Tom has ripped the boards off of the door after noticing that there is a phone booth inside, Tom peers inside, and yells "I can see the booth", but this line was obviously added post production because the line is spoken a lot clearer, and it's not Tom's voice. Also, if you look real close, Tom doesn't move his lips.
Crew and camera cranes visible in overhead shot of four "hot rods" chasing the family.
It's Winter in Massachusetts, yet the trees, shrubs and grass outside the hospital after Dana Andrews' accident are lush & green.