When the climate goes feral

All the sawmill’s forest is lost in devastating fires. After years of drought, a period of torrential rain breaks out. The barren slopes no longer hold water, and a black tidal wave rages through the river valley.
Eleven-year-old Mindra and her invalid grandmother are the last inhabitants of a village near the abandoned sawmill, high on the mountainside.
She rescues some survivors, who become her new family.
The world is tipping and they must make it on their own.