What rainy season? Southern California sees little relief on drought

For much of Southern California, this was another rainy season that wasn’t.

Dry, brown hillsides are testament to the fact that virtually the entire region has received less-than-average rainfall since the current water year started in October, with many areas 30-60% below typical.

April and early May tend to be the region’s last chance for any meaningful precipitation before the long, hot summer sets in, dashing hopes that the drought that began 2 1/2 years ago will end anytime soon.

“The year ahead is not looking good at all,” said Mehdi Nemati, an assistant professor at UC Riverside who specializes in water resource economics and policy, and works with water utilities in Southern California.

Weather forecasters are predicting above-normal temperatures and below-normal precipitation through the summer, as a La Niña pattern in the Pacific Ocean remains stubbornly in place. However, Southern California could see more monsoonal moisture than usual in July and August, which could help keep large fires at bay, according to the most recent local outlook from federal meteorologists.

Just how dry is it?

When this rainy season started in October, nearly 90% of California was experiencing extreme or exceptional drought, according to the U.S. Drought Monitor.

Officials had expected this winter to be dry because of La Niña, but December defied those expectations — downtown Los Angeles got about 9.5 inches of rain, almost triple the usual amount for that month, while Santa Ana and Riverside got almost double their usual December rainfall.

Then the skies dried out. For the next three months, almost no precipitation fell.

“That’s pretty rare,” said Brian Adams, a meteorologist with the National Weather Service in San Diego.

For California as a whole, January, February and March of 2022 experienced the lowest precipitation on record, according to the state Department of Water Resources.

It was also historically dry at four local weather stations that have been measuring rainfall for at least a century — at USC near downtown L.A., at the fire stations in Santa Ana and Riverside, and in Redlands.

A Southern California News Group analysis showed that those three months were the seventh-driest on record in downtown Los Angeles, fifth-driest in Riverside and fourth-driest in Santa Ana and Redlands. (The analysis excluded years that had too much missing data to show accurate totals.)

December’s rain eased the state’s harshest drought conditions, but they’ve been spreading back out ever since. As of this week, about 95% of the state is in severe or extreme drought, according to the Drought Monitor.

The 5% only in moderate drought takes in most of Orange and San Diego counties, western Riverside County and a sliver of southwest San Bernardino County. But that territory continues to shrink.

Summer isn’t the time for a drought to break. In a normal year, Southern California gets less than an inch of rain from May to September.

This compilation of U.S. Drought Monitor maps from October 2019 to May 2022 shows how the current drought has spread across California. Bright yellow represents abnormally dry conditions while orange and red show moderate to exceptional drought.
This compilation of U.S. Drought Monitor maps from October 2019 to May 2022 shows how the current drought has spread across California. Bright yellow represents abnormally dry conditions while orange and red show moderate to exceptional drought.

Fire outlook

Southern California actually has two rain-related factors going in its favor for this summer’s fire season.

May and June tend to be grass fire season, and Adams said the moisture content in the region’s light vegetation has been dropping. But because it was such a dry year, not much light vegetation grew, meaning there’s less of it available to catch fire. That’s why officials are predicting normal or below-normal fire activity during this period, said Rob Krohn, a Riverside-based meteorologist for the Bureau of Land Management.

The other favorable factor is monsoon season, which hits the Southwest U.S. in July and August. Forecasters are expecting more showers and thunderstorms than usual.

“That would bode well for a little less wildfire activity at higher elevations,” Krohn said.

But he said it would take a “colossal” thunderstorm season to have an impact on the drought — it’s winter storms and the snowpack that fill up California’s reservoirs.

Also, forecasters are expecting the monsoons to bring more lightning than moisture to Northern California, which is one reason that part of the state is expected to have above-normal fire activity this summer.

Peak fire season comes in September and October, when fuel moisture is at its lowest and Santa Ana winds are at their strongest. Krohn said that at this point, forecasters don’t have much of an indication whether this fall will be a strong Santa Ana wind season.

Water conservation

The drought recently forced Southern California’s water wholesaler to take emergency action, imposing unprecedented limits on outdoor watering for about 6 million people in Los Angeles, Ventura and San Bernardino counties. Those restrictions will take effect June 1, and the Metropolitan Water District is asking all Southern Californians to slash their water use by 30%.

Nemati, the UCR water resources expert, believes that will be a difficult challenge.

That’s because Southern California already has been one of the most successful places in the world at reducing water use over the past 20 to 30 years or so, he said.

In the 2012-2016 drought, there was a huge push to cut back as much as possible, and Californians responded. When the drought broke in 2017, some of that water use rebounded, Nemati said, but some of those reductions were permanent.

“So it’s getting harder and harder — even if there are new mandates, I don’t know how much they are going to be effective, because we already got rid of the low-hanging fruit,” he said.

He said Southern California water agencies did a good job in 2017-2019 at essentially saving back up for a non-rainy day — refilling reservoirs, diversifying their water sources, thinking ahead — so they were well prepared when the drought came back in 2020. But as the drought drags on, there’s only so long those savings can last.

Nemati said he expects more mandates and restrictions to be issued over the next year, and as much as he said water agencies try to keep water affordable for their customers, prices could climb higher, too.

“I think as we move forward, we’re going to see more expensive water rates regardless,” he said, because water sources are going to get more expensive, and persistent drought conditions are just making that happen faster.

“That’s the thing I’m most concerned about: How to keep water affordable and update infrastructure to prepare for droughts,” Nemati said.

‘We need to adapt’

California has been in a statewide drought for 11 of the past 16 years, and the whole western U.S. has been in a 22-year “megadrought” that’s believed to be the most severe drought in at least the past 1,200 years, as far back as tree ring records can show.

“We need to stop talking and stop thinking about drought as an emergency that happens once in a while,” said Jeanine Jones, the drought manager for the California Department of Water Resources.

As the environment becomes hotter and drier, “We need to adapt our infrastructure … to deal with hydrology that is quite a bit different than what we had in the past.”

Jones also said more investment is needed to improve long-term forecasting ability, so water managers can be better prepared. As it is, forecasters have a hard time peering more than a few months into the future,

When it comes to the current drought, forecasters see a good chance that the La Niña pattern will continue at least through summer, but Adams of the National Weather Service said beyond August or September, it gets trickier to say.

And it won’t be enough just for La Niña to end, he said — we’re going to need the rainy El Niño patterns to return for this drought to finally break.

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