The wet-weather forecast to last for the majority of this week is the type that experts say should be expected all winter.
The forecast for the next seven days warns of periods of heavy rains, walloping winds and large ocean swells as the result of several storms that are threatening to flood city streets, creeks and streams and cause widespread power outages for much of the Bay Area.
It’ll be great for skiers since forecasters are expecting 5 to 10 inches of snow in the Sierra Nevada, meteorologist Dave Reynolds said.
The storm will also help drench a thirsty state that has been weathering a three-year drought, though Reynolds warned not to get too excited.
“It’s hard to say you could cure the drought in one season,” he said, adding that 3 to 5 inches of rain on the coast is a conservative estimate for what’s to come in the next seven days.
More of this kind of weather may very well continue between January and spring, Reynolds said. That’s due to the return of a potentially strong El Niño — the periodic warming of the tropical Pacific Ocean that can influence severe weather in the Bay Area, inviting not only flooding but landslides as well, according to the National Weather Service.
“The history of El Niño is that it brings the Portland-Seattle weather down to California,” Reynolds said.
The most recent El Niño occurred in 2006, but was considered weak by scientific standards. In late 1997 and early 1998, however, a powerful version helped trounce downtown San Francisco with 47 inches of seasonal rainfall, which was more than double the average, according to data compiled by Golden Gate Weather Services.
Then again, “there have been El Niño winters where we’ve had drought,” Reynolds said.
“There are no guarantees,” he said. “It’s too early to say right now how
El Niño will materialize. It’s better to be prepared then not prepared.”
City officials have already begun preparing for storm consequences. On Friday, the San Francisco Public Utilities Commission and Department of Public Works issued a flood risk alert. The agencies advised that buildings in low-lying flood-prone areas should put out sandbags and report any blocked or clogged storm drains or catch basins.
Reynolds also warned that folks should not venture too close to the ocean coastline.
“We lose more people … out of the rocks looking for big waves than we do on almost any other weather phenomena in California,” he said.
Pull out the umbrella
The winter outlook from the National Weather Service calls for wet weather because …
- There is an expected moderate-strength El Niño condition that may persist through spring.
- El Niño could bring recurring storms with wet and windy conditions, such as the weather forecasted for this week.
- The forecast for Monday through Friday includes large amounts of rain, heavy snow in the Sierra Nevada, strong west and southwesterly winds.
- The weather patterns from El Niño may not become evident until January.