Could it be 2012 all over again? That’s the year Santa Rosa was drenched by nearly 10 inches of rain in December before Mother Nature abruptly turned off the tap, continuing the three-year drought that still hasn’t ended, despite another soggy December.
With rain falling on 13 of the month’s first 15 days and now totaling 10.64 inches, folks who may be tiring of cloudbursts, gray skies, umbrellas and last week’s atmospheric river could well be wondering if the drought is done.
Not until the Sierra is blanketed in snow and the state’s major reservoirs are full, water managers said Monday, noting that neither of those drought-busting conditions is close to reality.
“We’re having a great, wet December. It’s fantastic,” said Brad Sherwood, spokesman for the Sonoma County Water Agency, which delivers Russian River water to 600,000 customers in Sonoma and Marin counties.
The latest storm dropped 1.3 inches of rain on Santa Rosa during the 24-hour period ending at 4 p.m. Monday, and more rain is expected to hit the area today and Wednesday, potentially bringing an additional 2 inches, the National Weather Service forecast.
But California, with 80 percent of the state under extreme or exceptional drought last week, needs sustained precipitation through the winter and spring to make up for a 36-month shortfall.
“It’s a deep hole to climb out of,” said Samantha Dorsey, farming manager at McEvoy Ranch in the Marin County hills west of Petaluma.
All six irrigation ponds at the 550-acre olive and grape ranch were full and overflowing into San Antonio Creek on Monday, she said. A month ago, the ponds were 31 percent full. Dorsey said she felt a “tremendous sense of relief,” tempered by the concern that rainfall is still only one-third of normal and more is needed to maintain soil moisture for the 2015 crop.
Santa Rosa’s rainfall deficit — the difference between actual and average precipitation — was 34.53 inches for the period from December 2011 through Sunday, said Jake Crouch, a climate scientist with the National Climatic Data Center, a National Oceanic and Atmospheric Administration agency.
That means it would take nearly an average season’s rainfall, which is 36.28 inches in Santa Rosa, to balance the shortfall on local rain gauges.
“Basically, you’re missing a year of rainfall,” Crouch said.
But December’s storms made a dent, he said, noting that the three-year precipitation deficit at the end of November was 41.43 inches, the largest deficit ever for Santa Rosa and nearly double the statewide deficit of 23.5 inches. The past three years are the driest in California weather history dating back 120 years and one wet month won’t blot out the deficit.
Wetter areas like Sonoma County amass larger rainfall deficits than arid areas like San Diego, which typically get scant precipitation, Crouch said.
Thursday’s deluge, which flooded downtown Healdsburg and local roads, accompanied by winds that tore down trees and cut off power, accounted for 5.13 inches of rain in Santa Rosa, nearly half of the month’s total to date.
December is typically the city’s second-wettest month, with an average of 7.03 inches of rain, falling fractionally behind January’s average of 7.05 inches.
But Sherwood recalled the especially wet December of 2012, when Santa Rosa received 9.86 inches of rain, followed by a paltry 1.16 inches in January 2013 and leading to a meager 8.71 inches for that year.