Is Southern California Still in a Drought?

In the wake of the vicious rainstorms lashing much of California and causing millions of dollars of damage and flooding thousands of people's homes, many areas of the state are slowly coming out of drought conditions.

While the storms have affected Northern California the worst, with at least 17 people killed, Southern California has also received its fair share of rain. The Los Angeles Times reported that Los Angeles County experienced 2 to 6 inches of rain along the coast, with around 8 inches in the mountains. A further half-inch to 1.5 inches may still be on its way.

The rain has helped to alleviate some of the state's severe drought. The highest level of drought classification of the U.S. Drought Monitor—"exceptional drought—has disappeared in the past two weeks. Seven percent of the state was in this category on December 27, but this has dropped to 0 percent, as of January 3 data.

While much of that change occurred in areas of Central and Northern California, Southern California, which comprises 10 of California's 58 counties, including Los Angeles, Orange, Riverside, San Bernardino, San Diego and Santa Barbara counties, has also experienced drought reductions.

U.S. Drought Monitor data shows that since October 2022, when 99.77 percent of the state was under drought conditions, small slivers of the state have been declared drought-free. As of the most recent data, 97.93 percent of California is under drought, meaning that 2.07 percent is now classified as only "abnormally dry."

One of the areas of "abnormally dry" conditions is in the far south of the state, spanning Imperial County and a tiny section of Riverside County.

Additionally, many reservoirs in Southern California have seen increases in their water levels in the past weeks. Castaic Lake, a reservoir in the northwest of Los Angeles County, had a water level of 1,408.66 feet above sea level on December 25. As of January 10, this had increased to 1,424.32 feet. Lake Cachuma in Santa Barbara County saw an increase from 692.95 feet to 699.48 feet above sea level between December 25 and January 8.

More rain is forecast for the coming days, which may further pull parts of the state out of drought.

"The recent rains are very important in helping to prevent another dry year," Richard Luthy, a professor of civil and environmental engineering and a water infrastructure expert at Stanford University, previously told Newsweek.

He said 2020, 2021 and 2022 "were exceptionally dry years. In 2022, January, February and March, normally wet months, were the driest since records were kept in the late 1800s."

However, despite all the rain, scientists say that a lot more water is required to fully replenish the state's crucial reservoirs as well as the important groundwater supply.

"So far, the rainfall in the northern Sierra Nevada, which our largest reservoirs depend on, is at about 40 percent of the annual average," Roger Bales, a water and climate engineer at the University of California, Merced, previously told Newsweek. "We need more precipitation, closer to the average, to "refill" the reservoirs. We need two to three more big storms in January-March."

The rate of rainfall also matters, because if rain falls too quickly and inconsistently, the water just runs straight into the sea.

"All the rain at once means that much of it will run off into the ocean instead of filling California's reservoirs," Jacob Petersen-Perlman, a water resources geography expert and an assistant professor at East Carolina University, previously told Newsweek. "Second, if it continues to rain like it has been raining in California but not enough snow falls in the Sierras, drought may still persist."

Additionally, the wet weather may not last much past January, meaning that the coming summer could lead to conditions just as dry as those seen in 2022.

"We are hopeful that the reservoirs will be full at the end of this season. We just need several more big storms," Luthy said. "But it's hard to predict several months into the future. After a wet December in 2021, spring 2022 was a big disappointment."

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