The Mitchells had not left their home because their house was under a voluntary evacuation order and not a mandatory order, Weimer said.
Authorities have not confirmed the names of the dead.
Santa Barbara County Fire Search Dog Reilly looks for victims in damaged and destroyed homes in Montecito.
The death toll remains at 15, with 24 people missing.
In December, California Governor Jerry Brown said the state was "facing a new reality" as climate change meant wildfires could erupt "every year or every few years".
"He said so many times that after his passing, 'Make sure everyone prays for my soul.' We will, Roy!"
He was two blocks from home when he heard a rumble that he realized was the mudslide he feared. Kagel Canyon resident Patricia Beckmann Wells told the Los Angeles Times she expects to be trapped in her neighborhood.
"I looked out my front window and saw my vehicle fly by", he said.
"I just want to find my friend", Brewer said, in tears.
Winfrey posted a photo of mud in her backyard. "You can not imagine what it's like to be at the bottom of a funnel of literally acre-feet of watery mud, and it comes very, very fast".
She added: "It was always a full a life with Josie".
"And there are families missing, there are people who are missing family members.it's catastrophic". Many turned to social media in their search.
Rebecca Riskin, the founder of Riskin Partners, was killed when mudslides ripped through Montecito.
Riskin began selling real estate in Los Angeles.
Peter Hartmann said the destruction was everywhere.
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"There were gas mains that had popped, where you could hear the hissing", he told the TV station. The large aluminum poles to hold those were snapped in half.
Because hundreds of thousands of acres were charred in the fires, the influx of water has nowhere to go.
With heavy rain forecast, authorities had ordered evacuations beneath the burned areas of Santa Barbara, Ventura and Los Angeles counties, but only 10 to 15 percent of residents heeded the orders, according to the Santa Barbara police department.
Many residents probably couldn't grasp the scope of how unsafe mudslides can become, McNary told PBS NewsHour. They are asking people to "stay out of the area so that rescuers can do their job".
At least two deaths were blamed on the storm and mudslides in Santa Barbara County, the hardest-hit county in the area, County Supervisor Janet Wolf said in a telephone interview.
Search teams have worked around the clock, locating the dead, rescuing others and evacuating those who were simply stuck in homes but otherwise unharmed.
She and her family were trapped in their home by the mud and debris.
"There used to be a fence right here".
"If our house was flooded it would be devastating". Winfrey said debris is "everywhere".
The caption reads, "Thanks everyone for your prayers and concern".
She said her home had minor damage, but it pales in comparison to what her her neighbors suffered.
Much of the affected area is land scorched by the massive Thomas fire last month, where there is no vegetation to soak up the excess water.
One man, who wished only to be identified as Mikey, trudged through the Montecito mud with a shovel in hand. Long term, one option would be more basins to slow down storm runoff and collect debris.
Torrential rainfall contributed to damaging mudslides and flooding in Southern California on Tuesday. "They've been working 24 hours a day".
Santa Barbara County Fire Department firefighters respond to mud and debris flow due to heavy rain in Montecito.
The number of fatalities surpassed the death toll from a California mudslide on January 10, 2005, when 10 people were killed as a hillside gave way in the town of La Conchita, less than 20 miles (30 km) south of the latest disaster.