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Dry conditions in Southern California in early January 2025 set the stage for a series of deadly wind-driven wildfires that burned thousands of homes and other structures in the Los Angeles area.
Ming stovehydrologist at the University of California-San Diego Center for Western Weather and Water Extremestracks state water supplies. He put Southern California’s drought into perspective using graphs and maps.
How dry is Southern California right now?
In early January, soil moisture across much of Southern California was in the bottom 2 percent of historical records for this day in the region. This is extremely weak.
California hydrologists monitor the skies very closely from Octoberwhen the year of water begins in California.
The state receives very little rain from May to September. Late fall and winter are therefore crucial for filling reservoirs and building up the snowpack to provide water. California is counting on the Sierra’s snowpack accounts for about a third of its fresh water supply.
However, Southern California started the 2024-2025 water year rather dry. The area received some rain from an atmospheric river in November, but not much. After that, most atmospheric rivers which hit the West Coast from October to January, traveled north to Washington, Oregon and Northern California.
When the air is hot and dry, sweating and evaporation also draws water from plants and soil. This leaves dry vegetation that can provide fuel for flying embers to spread forest firesas the Los Angeles area saw in early January.
