Sol Survivors 2: Nashville Nightmare. Sol Survivors, #2

Forty days. That's how long it's been since the largest solar storm ever observed, now referred to as Helios, decimated modern civilization and released a polarizing nervous disorder into the human population. For diurnals like Joel McConnell and his odd assortment of guests, it means an all-out effort at self-sufficient living and keeping the local nocturnal population from stealing everything they produce. With military law enforcement busy saving terrorized citizens from the cadaverous remains of large cities, rural suburbanites such as Joel's clan find they must fend for themselves and settle their own problems.
Thanks in part to a cooperative trading post he established, which is starting to gain notoriety beyond their own neighborhood, Joel is managing to mostly keep peace. Until, he learns, he must make a daunting rescue attempt which leads him into the heart of what has become the darkest and most dangerous abyss in the entire south. A place many who escaped it refer to as the demon's dump. Most know it by its former name: Nashville.