What will California’s water picture look like in the next 12 months? The predictions are literally all over the map.
After a measurement of the snowpack in the Sierra Nevada on Tuesday, Jan. 2 found only 7.5 inches of snow — 30 percent of the average depth — the state Department of Water Resources (DWR) put out a statement saying residents should prepare for “flood or dry conditions in the months ahead.”
Why the cover all bases announcement?
Experts say that California’s unpredictable weather, coupled with warmer temperatures from climate change creating more rain than snow, makes the forecast cloudy with a chance of anything. Throw in a strong El Niño in the eastern Pacific and the predictions become even more varied.
Southern California water agencies are watching these developments because the snowpack in Northern California, once it melts in spring and summer, is where the state gets a third of its water supply — and much of that goes to the more populated southern half of the state. The snowpack feeds the reservoirs, which send water down the State Water Project (SWP), which provides 29 public water agencies serving 27 million California residents.
On Dec. 1, the state announced it would only allocate 10% of the orders for water to agencies dependent on Northern California water, who include most water agencies in Southern California. Experts say with more storms coming this month and in February and March, the percentage of allocated water should go up.
“We often get a slow start to our water year,” said DWR lead climatologist Michael Anderson. “A lot can change when we get to April 1. For now, just stay tuned.”
But on Tuesday, that didn’t stop Metropolitan Water District of Southern California, the nation’s largest wholesaler of water that is reliant on the NorCal snowmelt, from being concerned about drought conditions in 2024.
“Conservation must remain a way of life for all Californians, regardless of the weather. As water managers, we also must do our part by planning for a drier, more challenging future due to our changing climate,” wrote Adel Hagekhalil, general manager, in a prepared statement.
Water storage from last year’s deluge has filled up reservoirs. The Diamond Valley Lake Reservoir in Hemet is at 93% capacity, or 130% of its historic average, said Demitry Polyzos, section manager of MWD’s Water Resources Management Group on Wednesday. Shasta Lake is 69% full, or 116% of its historic average; Oroville in Butte County is 68% full, or 130% of its historic average.
“For Southern California going into this year, time will tell. But we’ve done a lot to prepare ourselves should it be dry, by collecting as much water as we could last year,” Polyzos said.
First wet, now dry
The contrast between January of this year vs. last year is stark, a 25% statewide snowpack average versus a whopping 185% last year when California experienced atmospheric river storms that flooded streets and covered the mountains in white powder.
“A weather whiplash is becoming the new normal,” said Bob Muir, MWD spokesperson on Wednesday. “This is a kind of threat.”
He said MWD has prepared a climate adaptation plan to deal with water variability from Northern California. Last year, the agency also worked with land owners in the San Joaquin Valley to store surplus water underground as ground water — water that would have gone to waste.
See-sawing precipitation levels has happened before and is what Anderson called “wild variability” in weather patterns. As an example, he said, “1977 was one of the driest years and 1978 was one of the wettest years.”
Another variable is the type of storms. If they’re blowing in from the tropics, they are warmer and produce more rain than snow and that doesn’t feed the State Water Project. Storms from the Gulf of Alaska are colder and drop snow in the higher elevations that turn into snowmelt, Anderson said.
So what about the storm heading into California over the coming weekend? Anderson said the storm lacks moisture so he’s not expecting an overwhelming amount of snow in the Sierras, nor much rain in Southern California.
As of Dec. 31, California precipitation is at 66% of average. Los Angeles has reached 80%, a sign that the storms are producing more rain than snow.
However, there will be snow on Donner Summit, where UC Berkeley lead scientist and director of the Central Sierra Snow Lab, Andrew Schwartz, will measure the snowfall. He predicts up to two feet of new snow will fall during the weekend storm.
“It probably won’t take us up to average for snowpack or precipitation but it will definitely help,” Schwartz said.
What about the El Niño?
DWR Director Karla Nemeth remained hopeful that the El Niño pattern will produce rain and snow and lots of it. But again, she hedges her bets, saying it’s still possible that won’t happen, and instead residents must plan for dry weather and put conservation measures in place.
Some are holding up El Niño as a harbinger of wet weather. But again, even an El Niño doesn’t guarantee rain in Southern California or snow in the Sierra Nevada.
William Patzert, retired oceanographer and climatologist from Jet Propulsion Laboratory in Pasadena, is one of the foremost experts on weather patterns, both the dry kind and the wet kind. On Wednesday, he said El Niños make it rain in Southern California two out of three times — not every time.
In 2016, he predicted a “Godzilla El Nino” for Southern California. But it missed the region. Instead, it flooded Northern Mexico and the Gulf Coast regions, he said.
Already, the current El Niño is bringing monsoons to India and flooding to Australia. Rainy weather flooded parts of Ventura County, but that water doesn’t get captured, he said.
“The dice is loaded for an above average rainfall and big snowpack in the Sierras,” Patzert said, adding this caveat: “Even if California doesn’t get that, somewhere else will get it.”
The fickle El Niño pattern, which usually shows up around Christmas time, translates as “The Child” as a reference to the Christ child. During past El Niños, the region had five of its highest snowfalls but also four of its lowest snowfall patterns, said Schwartz — .showing that the weather patterns are unpredictable in California.
“Normal is a cycle on a washing machine. Be careful when you say ‘normal,’ ” Patzert said.
