The Waking Dark by Robin Wasserman
The town of Oleander is postcard perfect.
Until one day.
The day the Devil came to Oleander.
Whatever they called it, through the months to come - through the funerals and the dinners and the sidelong glances between formerly trusting neighbours - it was all anyone could talk about. It seemed safe to assume it was all anyone would ever talk about, just as it was assumed that Oleander had been changed for ever, and that, once buried, the bodies would stay in the ground.
But then the storms came . . .