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Ming Lordhydrologist from the University of California, San Diego The center of western weather and water extremestracks the state’s water supply. He put the aridity of Southern California into perspective using charts and maps.
How dehydrated is it in Southern California right now?
In early January, soil moisture in much of southern California was around in the bottom 2 percent of historical records for this day in the region. It’s very little.
Hydrologists in California watch the sky very carefully starting in OctoberWhen does the water year start in California?
There is very little rainfall in the state from May to September, so tardy fall and winter are crucial to filling reservoirs and rebuilding the snowpack that provides water. California relies the Sierra snowpack, which accounts for about one-third of its freshwater resources.
However, Southern California started the 2024–25 water year quite dehydrated. In November, the region experienced rainfall from the atmospheric river, but not in enormous amounts. Then most of it atmospheric rivers that hit the West Coast from October to January headed north to Washington, Oregon and Northern California.
When the air is toasty and dehydrated, transpiration evaporation also sucks water out of plants and soil. This leaves dehydrated vegetation that can provide fuel flying embers that spread firesas happened in early January in the Los Angeles area.
