El Niño forecast boosts hopes for wet season on North Coast
Battered by a historic drought that has fed raging wildfires, shrunk reservoirs and prompted water curtailments and conservation mandates, Californians are yearning for relief.
It can only come from the skies, and now, with winter on its way, the question on the minds of more than 38 million Golden State residents is: Can El Niño, the weather phenomenon named for the Christ child, deliver meteorological salvation across the land, from the arid south to the normally damp north?
For the North Bay, where that answer is still highly anticipated, a shortfall on the wet forecast may not portend an immediately deepening disaster, as it could for much of the rest of the state.
The region draws its water from the Russian River and local wells, independent from the Sierra Nevada snowpack — the lowest in recorded history last winter — and the state’s major reservoirs, now 70 percent to 90 percent empty.
The North Bay’s major reservoir, Lake Sonoma, with a two-to-three-year supply when full, remains at more than 70 percent of its capacity.
Just an average amount of rainfall over the next six months in Santa Rosa — about 36 inches — would go a long way toward topping off that supply and other local reservoirs, significantly easing drought in the region, if not ending it, said managers of the Sonoma County Water Agency, the primary source of water for 600,000 North Bay customers.
“If we could get that, we’d be doing OK,” said Pam Jeane, the Water Agency’s assistant general manager.
To make up for its accumulated deficit from the four-year drought, Santa Rosa would need an additional 30 inches — a soaking that would flirt with or break records but also risk significant damage if it came in a single season.
Water managers are wary of that possibility.
“It would be great if we could get more, but we don’t want it all at once,” Jeane said.
In Valley Ford, beef and cattle rancher Joe Pozzi would like rain to fall soon, greening his pastures while the soil is still warm and continuing through spring, replenishing farm ponds. That would be ideal, he said, “but at this point, we’ll take whatever we can get.”
As it stands, El Niño is muscling up in the Pacific Ocean around the equator, renewing the prospect of a wet California winter. While that forecast fizzled last year, this year there is a 95 percent chance that El Niño will continue through the winter before gradually weakening in the spring, according to the latest federal forecast.
“El Niño hype is in full swing,” said Jan Null, a consulting meteorologist, referring to advertisements urging people to buy ski passes and make sure their roofs are ready for winter.
El Niño ‘misunderstood’
There’s some basis for anticipation, given that the El Niño is on par with California’s last very strong event, Null said, which delivered 167 percent of normal rainfall statewide and 154 percent to the North Coast region from Marin County to the Oregon border in 1997 and ’98.
But El Niño’s track record — with 23 events since 1950 in California — is mixed. A dozen have been classified as weak, six as moderate and only five as strong or very strong, with an average yield of just 105 percent of normal rainfall. The likelihood of heavy rain increases with the strength of an El Niño, but two of the three strong events delivered below-average precipitation on the North Coast while a weak event in 1994-95 dropped 143 percent of average rain, the fourth highest rainfall ever.