Minimal snow at the Phillips Station meadow near Lake Taho in January 2018 presaged the last drought year. Photo by Kelly M. Grow for California Department of Water Resources

Scientists at the University of Southern California are predicting an unusually warm and dry winter for California.

Lowell Stott, a professor of Earth sciences at the Dornsife College of Letters, Arts and Sciences, said in a news release on Wednesday that La Niña conditions developing this winter in the equatorial Pacific Ocean will cause warmer temperatures and drier conditions across the entire Southwest.

“There’s a good chance this winter will be drier and warmer than average. This is likely to affect the Sierra Nevada snowpack and the timing of spring runoff, which can lead to trouble next year with the water supply in California,” Stott said.

According to USC scientists, forecast models predict a 90% likelihood of La Niña conditions — a period of below-average sea-surface temperatures across the east-central Equatorial Pacific.

But California could still get a number of heavy storms, so-called “atmospheric rivers” that can dump an enormous amount of moisture in a short period and damage areas devastated by wildfires.

Josh West, a professor of geology at USC Dornsife, said he is concerned about that possibility.

“So much land burned this year across California and the West that we have heightened risk for damaging debris flows,” West said. “We’ve dodged a bullet so far because it’s dry, but that could change with big storms.”

California’s last major period of drought ended in early 2019.

Chris Jennewein

Chris Jennewein is Editor & Publisher of Times of San Diego.