California saw a dizzying turn from a dry February to a wet start to March, but federal climate experts say the recent snow and rain won’t halt the state’s continuing slide into drought.
The U.S. Spring Outlook, released by the National Oceanic and Atmospheric Administration on Thursday, projects that warm, dry conditions will persist and even expand across much of California over the next three months. Already, nearly half of the state is considered in moderate drought.
While water supplies remain at comfortable levels — that’s the product of several years of precipitation collected in the state’s big reservoirs — federal officials warn that the drying hills and valleys this spring could lead to an early fire season.
“When you miss out on January and February, the two wettest months of the year, it’s hard to recover from that,” said David Miskus, meteorologist at NOAA’s Climate Prediction Center in College Park, Md. “You’re heading into your dry season now.”
The below-average precipitation this winter, including a rainless February for much of California, means that the state’s wet season will go down as one of the 10 driest in nearly a century, depending on where you measure, according to state records. San Francisco has received 10 inches of rain since October, half of what it usually sees in that time.
The forecast for a warm, dry spring comes in contrast to the heavy rain and flooding expected in much of the United States. About 128 million people across 23 states, from the Gulf Coast to the Northern Plains, are at risk of dangerous rainstorms over the next three months, federal officials reported. This comes after parts of the Midwest saw a historically wet 2019.
“We anticipate that nearly one-third of the country will experience some level of flooding this year,” said Ed Clark, director of NOAA’s National Water Center in Tuscaloosa, Ala.
The sharp difference in weather between the West and the East has been a common refrain in recent years. The drought in California that began around 2012, for example, came as much of the eastern seaboard was socked with rain and snow.
It’s a pattern that climate experts tie to shifts in the jet stream, which is pushing east-moving storms away from California and into the heart of the country. The change, they suspect, may be caused by warming temperatures in the Arctic.
“We’re actually working to quantify this,” said Deke Arndt, chief of NOAA’s Climate Monitoring Branch at the National Centers for Environmental Information in Asheville, N.C. “In the last decade or so, we’ve seen more of these stuck patterns, where half the country is experiencing one regime and half is experiencing another.”
California is expected to see on-and-off rain for the remainder of March. The National Weather Service forecasts isolated showers for the northern part of the state into the weekend with the next significant storm arriving Sunday.
Mike Anderson, state climatologist at the California Department of Water Resources, said the soggy weather will do little to change the trajectory toward drought, even as several feet of snow hit the Sierra during this month’s big storms.
“As we move into spring, the storm track starts to head north and we shift into our dry season pattern,” he said.
The federal Drought Monitor reported Thursday that nearly 48% of California was in moderate drought, about the same as last week, despite the recent rain and snow. A chunk of Siskiyou County along the Oregon border slipped into severe drought. None of California was categorized as extreme or exceptional drought, which was the case for most of the state during parts of the five-year drought.
The snowpack in the Sierra, which helps gauge the amount of water that will drain into reservoirs, measured 49% of average on Thursday. The reservoirs, though, were at near average levels because of runoff from past winters.
California fire officials say they’re prepared for whatever the fire season brings this year, though the biggest challenge may not be the weather but the coronavirus outbreak. Emergency officials say evacuation centers set up during wildfires will be clean and offer extra space for evacuees to prevent the spread of the virus.
Anderson, the state climatologist, said the key for him is next year.
“We came into this year in good condition,” he said, noting that it’s been wet enough in California to stave off serious drought problems in the short term. “But is this a single dry year or another multi-year (drought)? We don’t have the capability to answer that.”
Kurtis Alexander is a San Francisco Chronicle staff writer. Email: email@example.com Twitter: @kurtisalexander