Continuity mistake: The mural outside of the apartment switches walls - it's on the right most of the time but it appears on the left in one scene. (00:30:48)
Continuity mistake: When the hitman tries to kill him while he is driving, he passes the silver Toyota Prius without making any contact, and 5 seconds later drives into the same Prius that had already passed. (01:09:25)
Continuity mistake: When McCall is about to have the fight in the hotel room, the man who answers the door goes and locks the door right before the fight begins. When McCall is done with the fight, he turns the doorknob and walks out without ever unlocking the door.
Continuity mistake: When Denzel is fighting with the assassin in the car, the driver's seat can is rotating between shots.
Continuity mistake: When he gets Miles from the gun gang, he has his own revolver and takes one from the guy at the elevator but when he enters the room he has an automatic weapon from nowhere.
Continuity mistake: When Robert enters the boss' room to pay for Teri's "freedom", before he goes to leave, he turns the three glass skulls on the desk to face 3 of the gangsters. After he goes to the door and locks it, he looks back at them and the skulls are now back in their original positions, facing forwards.
Continuity mistake: When fighting the guy in the back seat. Denzel initially swerved and passed the green Prius. They pass the same car again and hit it.
Answer: Extremely high winds from the storm. He was relatively protected lying down but blew backwards when he got up.