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Dry conditions across Southern California in early January 2025 set the stage for a series of deadly wind-driven wildfires that They burned thousands of houses and other structures in the Los Angeles area.
Pan Minghydrologist at the University of California-San Diego Center for Western Climate and Aquatic Extremestracks the state’s water supplies. He put the dryness of Southern California into perspective using charts and maps.
How dry is Southern California right now?
In early January, soil moisture in much of Southern California was in the bottom 2 percent of historical records for that day in the region. That is extremely low.
California hydrologists watch the sky closely starting in octoberwhen California’s water year begins.
The state receives very little rain from May to September, so late fall and winter are crucial for filling reservoirs and building up snowpack to provide water. California depends on The Sierra’s snowpack accounts for about a third of its freshwater supply.
However, Southern California started the 2024-25 water year fairly dry. In November the region received some rain from an atmospheric river, but not much. After that, most of the atmospheric rivers that hit the West Coast from October to January turned north toward Washington, Oregon and northern California.
When the air is warm and dry, perspiration and evaporation also absorb water from plants and soil. That leaves dry vegetation that can provide fuel for Flying embers to spread forest firesas the Los Angeles area saw in early January.