While the group watches the news, the television in the background shows the debris. The television freezes, but the dialog continues.
When they stop the truck to watch the ash fall, the wipers are not on, but you can hear windshield wiper sound effects.
Right before Jason and Ashley encounter Lynn and her daughter, they say they need water and a car. There is clearly a car in the background outside as this dialogue is being said, but they are never told to use that car nor do they seem to realize it is even there.