There is a 75 percent probability of average or above-average precipitation between January and the end of March for California, according to a new report by federal scientists — the first time in five years such a wet outlook has been predicted in the state during the first three months of a year.
“This is good news,” said Steve Baxter, a seasonal forecaster with the National Oceanic and Atmospheric Administration, which issued the report on Thursday predicting that the harsh reality of California’s historic drought may finally be giving way to wetter days ahead.
“There are not indications of a monster wet season,” he said. “It’s unlikely that the drought will be broken this year, but it’s likely that it will be improved.”
Pacific Ocean temperatures, which are warmer than normal, along with satellite imagery and computer models, are showing a greater likelihood of low-pressure systems, which can draw storms to California, Baxter said. There still is also a 65 percent chance of mild El Niño conditions developing this winter, which could further increase chances.
Meanwhile, reservoirs continued to slowly rise across Northern California after three weeks of drenching rains. And another report out Thursday also offered an additional glimmer of hope. The U.S. Drought Monitor, a weekly map issued by the U.S. Department of Agriculture and other agencies, showed that 32 percent of California is in “exceptional drought,” notably down from 55 percent last week, due to the recent rains.
The area showing improvement includes the Bay Area and communities from Monterey County to Humboldt County. Still, the Central Valley and the Los Angeles Basin, which have not received as much rain, remain in “exceptional drought.” And 98 percent of California is still in “severe drought,” the third most serious of five classifications.
But the update, which is based on soil moisture levels and other factors, was the first time in more than two years with such a large section of the state showing an improving trend.
“We’ve gone from real bad to just bad,” said Bob Benjamin, a forecaster with the National Weather Service in Monterey. “If we would have had any more rainfall in the last few weeks, we would have had some major flooding. The trend is moving in the right direction. We’re where we want to be. We need to keep it up into April.”
Weekend forecast
Looking ahead to the weekend, more rain is forecast for Friday, with half an inch or so in most Bay Area cities and one inch or more in the mountains. After that, Northern California can put away its umbrellas for about a week.
“We can expect dry conditions at least through Christmas Day,” said Benjamin. “People will be able to enjoy some sun.”
California is mired in one of its worst droughts in history and has been since 2011, with many parts of the state receiving only about half the rainfall as the historic average. As a result, when the winter rainy season began, reservoirs were at dangerously low levels, streams were dry and groundwater tables had fallen precipitously. Farmers and water planners were worrying of severe cutbacks and rationing if the state moved into a fourth year of below-normal rain in 2015.
That dire scenario still could play out if the wet weather stops.
But this winter season, so far, has begun with a deluge.
As of Wednesday night, San Jose’s rainfall total since July 1 was 10 inches — 253 percent of the historic average for this time of year. Similarly, San Francisco was at 193 percent, Oakland at 191 percent.
With the ground finally saturated, much of the rain is pouring into reservoirs. The state’s largest, Shasta Lake near Redding, has risen by 35 feet since Thanksgiving, adding 448,000 acre feet of water — enough to supply every home and business in the city of Los Angeles for 10 months.
But in a clear illustration of how far California has to go to end the drought, all of that water only increased Shasta Lake from being 23 percent full three weeks ago to 33 percent full now.
“There have been some healthy rises, but it still has a long, long way to go to recover back to levels that we saw three years ago,” said Kevin Werner, NOAA’s western regional climate services director in Seattle.
Similarly, in the Bay Area, the 10 reservoirs operated by the Santa Clara Valley Water District, which serves 1.8 million people in and around San Jose, were 28 percent full weeks ago. After the storms, they are at 38 percent.
And the East Bay Municipal Utility District, which provides water to 1.4 million people in Alameda and Contra Costa counties, has seen its seven reservoirs increase from 52 percent full to 54 percent over the same time. The small increase is due to the fact that the district’s largest, Pardee Reservoir, is in the Central Sierra Nevada, which has not had as much rain and snow as the Northern Sierra.
“Of course the recent storms are helping, but after two very dry years, nearly half of our reservoir space is empty,” said Abby Figueroa, a spokeswoman for EBMUD. “We’d love it if Mother Nature would keep pouring it on.”
Suspended fines
Overall, the Sierra Nevada snowpack on Thursday was at 50 percent of the historic average for this date, up from 24 percent three weeks ago — climbing, but still half of where it should be.
In Santa Cruz, which has had some of the strictest water rationing rules in the state, city officials suspended the tough restrictions and fines earlier this month, asking instead for voluntary conservation. The city’s only large reservoir, Loch Lomond, near Ben Lomond, has risen 6 feet — from 58 percent full to 67 percent full — in the past three weeks, as the watershed around it has received 24 inches of rain so far, compared with 2 inches this time last year.
The recent rains, combined with Thursday’s federal reports, offered Californians hope for more soaking storms. Water experts remembered 2012, however, when a wet November and December gave way to a bone-dry spring, and 2013 became the driest year in state history back to 1850.
Baxter, of NOAA’s Climate Prediction Center, in College Park, Maryland, said that chances of a similarly dry recurrence are not high. But because of the state’s huge rainfall deficits, he added, California will need every inch of rain it can get in the coming months.
“The rains that have occurred over the last month are good,” he said, “but they are not enough.”
Paul Rogers covers resources and environmental issues. Contact him at 408-920-5045. Follow him at Twitter.com/PaulRogersSJMN.
