Snubbing La Niña, Southern California defies predictions of a dry rainy season

Let us not scorn those forecasters who, months ago, so confidently predicted a drier-than-normal Southern California winter.

Instead, let’s calmly note that Sunday’s ferocious storm dumped so much water throughout the region that it shattered records in several communities. Downtown Los Angeles and many other areas have exceeded rainfall averages for an entire season — and there’s still three months to go.

“La Niña definitely was a bust,” said Bill Patzert, a climatologist at the Jet Propulsion Laboratory in La Cañada Flintridge and one of several meteorologists who had predicted last fall that La Niña, a climatological phenomenon marked by cold ocean-surface temperatures, would bring a drier-than-normal rainy season.

Photos: Southern California storm

The Arctic storm that passed through the region Sunday set daily rainfall records in many communities. In downtown Los Angeles, 2.42 inches had fallen by 8 a.m. Monday, about an inch more than the previous record set in 1943.

Los Angeles has logged about 181/2 inches since the rainy season began, 3 inches over its average for the whole season, said Stuart Seto of the National Weather Service in Oxnard.

More showers are forecast for Wednesday, Thursday and possibly Friday, though precipitation will be considerably lighter than Sunday’s deluge, Seto said.

Hurricane-force wind gusts up to 98 mph roared through mountain passes, while gusts between 50 and 60 mph toppled trees throughout Southern California’s urban landscape. Flowing mud swamped a retaining wall in Woodland Hills, forcing the overnight evacuation of 12 homes. Six remained affected Monday.

In hard-hit Santa Barbara County, sheriff’s deputies rescued 18 people who had become stranded near Nira Campground as rivers swelled into raging waters. In Ventura County, 26 hikers in five separate groups were rescued Sunday and Monday after friends reported them missing.

Also Monday, a group of five men from Orange County and two men hiking with a dog were found stranded in the Willett Hot Springs area and taken to safety.

A La Niña condition in the Pacific usually brings heavy rainfall to places such as Australia, Indonesia, Brazil and Colombia while bringing unusually dry periods to California and the southern United States. Texas and other southern states have been relatively dry, Patzert said.

But powerful storms originating in the Gulf of Alaska have nullified La Niña’s effect in the Southwest, he said.

“La Niña was real,” he said, “but she played second fiddle to all of these storms out of the North Pacific.”

La Niña still managed to wreak havoc on other parts of the planet, including serious flooding in Australia, forecasters said. And if the December rains hadn’t happened, the state would be recording lower-than-normal precipitation for the year, they said.

Photos: Southern California storm

Scientists measured oceanic and atmospheric conditions in February and found that La Niña was beginning to weaken, Patzert said. It’s still possible that the rest of the rainy season, after this week, will be dry, he said.

catherine.saillant@latimes.com