In your opening introduction to the characters, Jace Sanders goes ahead and crumbles the newspaper onto the table.
You then proceed to have your main character wad up the newspaper(both the same action, with different words) and have it thrown at Jace Sanders. The newspaper is already bunched up, and we can assume that the readers either have a long enough attention to span to remember that the newspaper was previously wadded up, or would have enough common sense to understand newspapers cannot be thrown if they are not wadded up. Like most flat materials.
"I kick open the door, and the lights on the inside of the car flick on."
Can you truly kick open a car door? I don't believe I've tried before, but it doesn't seem like the easiest thing to do. I would assume the character is opening the door; something that is performed with the hands, not the feet. Perhaps the car has an old quirk, and you have to unlatch the door before bringing your legs up and slamming on the side to open it. But only add things like that to the car if its necessary to the story. We don't want a clunker that offers nothing new to the plot. This draws attention to the car when it is not needed.
"I rummage through my things, through the lone baseballs and rolls of twine and empty grocery bags. "
Perhaps a more correct sentence here would be: I rummage through my things, the lone baseballs, rolls of twine, and empty grocery bags that litter the back of the car.
There still is a problem with the sentence though, the clutter is mentioned twice, when it should only be mentioned once.
"The forest is loud around us, filled with hooting owls and scampering squirrels and shuffling leaves."
We are still having the issue of too many "and"s, but this time we also have to pay attention to the around us. Is the forest only loud in the area that the characters are in? Are the owls making any other noise? the squirrels? Why are the squirrels and the owls awake at the same time? Its important to remember that some animals are nocturnal, and others are not.
"Jace’s eyes sweep up and around, shivering in his leather jacket. "
You quickly move from a description of Jace's eyes to his leather jacket. You may want to reconsider this, as it can be confusing and sounds like his eyes are shivering - not himself.
There is a lot more to talk about, but I feel like you haven't really found a defined sense of whether you are writing in first person or third person. I could be wrong, but I'm going to take a shot in the dark that you want to go into more description, but you can't because you are strongly limited by the first person perspective. First person is an excellent form of writing, and in the right hands it should never be discluded, but its much harder to master then third person.
The idea behind the story is good, don't get me wrong. Horrors have always been one of my favourite categories, but they are one of the hardest to execute(in my opinion). the question of when you reveal the villain, how much you reveal, and how the story ends. Those are all factors that need to be taken into heavy consideration.
The one thing you do get across is the point of the story, and for that I applaud you - but learning to fill in the detail and the space between will get you very far.