Outbreak - L. C. Mortimer - Bog

Emily thought she could survive the apocalypse and save her sister from hordes of undead. She was wrong. By the time she found her sister, it was too late. All hope was shattered. Heartbroken and disillusioned, Emily returns home. There's just one problem: her haven is no longer empty. Someone has moved in.
Neil was a leader long enough to know when to cut his losses. Surviving in the city was one major loss. He gathered his friends and hoofed it to the forest. He knew there would be abandoned farmhouses and plenty of land. The fewer inhabitants before the apocalypse struck, the fewer zombies to deal with after.
The house they find is incredible. It's isolated, well stocked with food, and Neil even finds a few loaded guns. Soon it becomes obvious that the home isn't as empty as they originally thought, however. When the owner returns, she demands that Neil and his friends move out. She seems to have no problem with the idea of tossing them out on their asses, but there's a major problem.
A storm is coming, and it carries with it a greater threat than just zombies.