These maps show how dry Southern California is right now
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Dry conditions across Southern California in early January 2025 set the stage for a series of deadly, wind-driven wildfires Thousands of houses and other buildings burned down in the Los Angeles area.
Ming PanHydrologist at the University of California-San Diego Center for Western Weather and Water Extremestracks the state’s water supply. He used diagrams and maps to put Southern California’s drought into perspective.
How dry is Southern California right now?
In early January, soil moisture levels were low across much of Southern California in the bottom 2 percent of historical records for this day in the region. That is extremely low.
Hydrologists in California are watching the sky closely from Octoberwhen California’s water year begins.
The state receives very little rain from May to September, so late fall and winter are critical to fill reservoirs and build snowpack for water supply. California relies on it The Sierra’s snowpack provides about a third of its freshwater supply.
However, Southern California began the 2024-25 water year fairly dry. The region received some rain from an atmospheric river in November, but not much. After that most of them atmospheric rivers which hit the West Coast from October to January, turned north to Washington, Oregon and northern California.
When the air is warm and dry, transpiration and evaporation also remove water from plants and the soil. This leaves behind dry vegetation that can be used as fuel flying embers to spread forest firesas the Los Angeles area saw in early January.
