The unrelenting grip of severe drought on Santa Barbara County may be about to loosen.
Forecasters say a series of winter storms expected to douse the region over the next several days could drop enough rain — possibly 6 inches or more — to cause significant runoff into nearly depleted Lake Cachuma.
“If we get hit as hard as they’re talking about, we could see substantial inflow to Cachuma for the first time since 2011,” said Tom Fayram, the county’s deputy water resources director.
While forecast models are no guarantee, in the best-case scenario, the level of Lake Cachuma could rise several feet, Fayram said. The reservoir is the South Coast’s major water source, so that rise would be a huge relief to local water purveyors.
The first storm is predicted to bring 1 to 2 inches of rain to most areas of the county Wednesday night into Thursday, according to Mike Wofford, a meteorologist with the National Weather Service in Oxnard.
A second, colder weather system, with similar rainfall potential, is expected to move through the region on Friday, Wofford said.
That storm could bring six to eight hours of moderate to heavy rainfall, mainly during the day, before it moves on to the east, Wofford said.
Snow levels from that system may drop as low as 3,000 feet of elevation, leaving a coating of the white stuff on local mountains.
That system also could bring gusty winds, Wofford said, adding that wind advisories are likely.
After a brief respite on Saturday, rain is expected to return Sunday into Monday, with a slower-moving weather system that could provide 1.5 to 3 inches of rain in most areas, and up to 5 inches in some locations, forecasters said.
The county expects to activate its cloud-seeding operation, Fayram said, utilizing both ground-based and aerial equipment in an effort to squeeze more precipitation from the storms.
Cachuma was just over 9 percent full on Tuesday, up slightly from its low point due to mild runoff from recent storms. The reservoir is more than 100 feet below spill level.
Beyond any beneficial effects to Cachuma, the storms could help refill Gibraltar Reservoir and Jameson Lake farther upstream on the Santa Ynez River.
Gibraltar, which was at 14.9 percent of capacity on Tuesday, provides water for the city of Santa Barbara, while Jameson, at 10.1 percent full, serves the Montecito Water District.
If these storms produce as advertised, they would only make a dent in the county’s water deficit, Fayram said, but would set the stage for additional storms later in the rain season.
“Back-to-back storms can define our water supply,” he added.
High temperatures the next few days are expected around 60 degrees, with overnight lows in the upper-40s.
Clear skies and a drying trend are expected beginning Tuesday, Wofford said.