Snowmelt Sparks Severe Flooding in California's Central Valley.

Unseasonably warm temperatures in California are causing the historic snowpack in the Sierra Nevada mountains to melt, leading to flooding in the Central Valley and threatening communities like Corcoran. The snowpack, which is more than three times the average, feeds into four major rivers that eventually empty into the Tulare Lake Basin. Local, state, and federal officials are preparing for the flood threat, which is expected to worsen in the coming weeks.