A WET ARRIVAL
Forecast of wind and rain will bring ‘ ugly all over the place’
The first major storm of the season barreled toward the Bay Area overnight, threatening to drench Friday morning’s commute, clog storm drains, topple trees and pound the coast with big waves through the weekend.
“We’re looking at a very strong storm for this time of year,” said Bob Benjamin, a forecaster with the National Weather Service in Monterey. “It’s going to be windy and ugly all over the place.”
The storm, driven by the remnants of Typhoon Songda, which pounded Japan last week, is on track to deliver 0.75 to 1.5 inches of rain to the San Francisco, San Jose, Oakland and Monterey Bay areas, with 2 to 4 inches in the Santa Cruz Mountains and Marin, Napa and Sonoma counties.
Put into context, the storm will likely deliver as much rain on Friday as the major Bay Area cities receive on average for the entire month of October.
This weekend also almost certainly will be the wettest in seven months in the Bay Area, since March 12, when San Francisco received 1.14 inches of rain, Oakland saw 0.88 and San Jose got 0.53.
The storm also will bring light snow to the Sierra Nevada, above 8,000 feet, according to the National Weather Service. Some parts of far Northern California, from Mount Shasta to Crescent City near the Oregon border, are expected to receive 6 to 12 inches of rain through
Sunday. A small-craft advisory is in effect from Big Sur to Point Arena, with swells expected as big as 14 to 16 feet starting Friday.
Benjamin said that roadways for the Friday morning commute will be slick, with leaves clogging storm drains, standing water on some highways and branches falling onto power lines.
“The first significant rainstorms lift the oil from the roads and make them slicker than heck,” he said. “That’s going to be a concern. And there will be reduced visibility. And the winds will probably bring down a few trees.”
PG&E officials said Thursday that they are closely tracking the weather.
“It’s a major storm,” said Abby Figueroa, a spokeswoman for PG&E. “We have meteorologists running storm damage models where we might have outages, so we are ready to go.”
Tree-trimming crews in recent days have put special emphasis on communities in Marin and Santa Cruz counties, she said, where blackouts have historically been common in early winter storms.
While the storm will do little to erase five years of drought, it will significantly reduce wildfire risk for the Bay Area for the rest of the month.
But in places where fires have burned recently, erosion is a major concern.
The Loma fire, which burned 4,474 acres and destroyed 12 homes in southern Santa Clara County in the mountains west of Morgan Hill, was declared 100 percent contained on Wednesday evening.
But the fire left a charred landscape on steep slopes near Uvas and Chesbro reservoirs.
“There’s a lot of loose soil and no vegetation,” said Patty Eaton, a spokeswoman for the Santa Clara Valley Open Space Authority, who toured the area Wednesday with officials from Cal Fire, the Santa Clara Valley Water District and other agencies.
“One of the water district guys said it could be like a marble rolling off glass,” she said. “We have property there, and it’s 1,500 acres of stumps and dead trees. There are carcasses of animals. It’s all burned out, hillside after hillside. The ground was still warm yesterday.”
With such a big area and so little time before rains come, there’s not time to do adequate erosion control work, she said, and debris could wash into reservoirs, not only fouling the water, but potentially clogging pipes and reducing their capacity to hold as much water.
What does the storm mean for California’s drought? Over the past year, Northern California has seen its best rainfall totals in five years. For the year ending Oct. 1, San Francisco received 23.1 inches, or 98 percent of the historic average; San Jose had 14.91 inches, or 94 percent; and Oakland received 20.85 inches, which was 87 percent of normal. Those rainfall totals helped boost reservoirs, leading Gov. Jerry Brown’s administration to lift mandatory water conservation targets statewide.
Southern California received far less rain in the past year than Northern California, and now many large reservoirs around the state remain below their historic levels for this time of year. Worse for Los Angeles and San Diego, this weekend’s storms won’t deliver much more than a light sprinkling south of San Luis Obispo, Benjamin said.
The storm is expected to bring rain across the Bay Area all day Friday, tapering off Saturday morning, then returning Saturday night into Sunday. Next week is forecast to be sunny and warmer.
On Thursday, in its monthly update, the National Oceanic and Atmospheric Administration announced that conditions are shaping up in the Pacific Ocean for a 71 percent chance of a La Niña developing by November. La Niñas result when water near the equator in the Pacific cools, the oppo- site of El Niño conditions. Historically, they have been loosely linked with lowerthan-average rainfalls for California, although some La Niña winters have brought normal, or even above-normal rainfall, experts say.
This weekend’s rains are part of an atmospheric river out of the Gulf of Alaska that will drench Seattle and Portland. They aren’t a “Pineapple Express” because they are coming from a cooler part of the Northern Pacific, said Benjamin. Nor should the wet weather be taken as a signal that the overall winter will be wet in California, Benjamin said. It’s simply too early to tell.
“It’s definitely a helpful event,” he said. “We’re off to a good start. Hopefully we can maintain this direction.”