Search for missing 79-year-old San Mateo Co. woman with dementia in Portola Valley hits Day 3

PORTOLA VALLEY, Calif. (KGO) -- The search for a missing Redwood City woman with dementia entered its third day on Saturday.

More than 100 search and rescue volunteers have joined the search effort for 79-Year-old Margaret Elaine McKinley at the Windy Hill Open Space Preserve in Portola Valley.

"There were a lot of search people in yellow vests, with dogs searching through brush on trails," said Martha Angell.

Angell, who is a hiker from Palo Alto, said she wasn't alone on her trek through Windy Hill Preserve Saturday. Dozens of search and rescue teams joined the search effort McKinley.

"As we hit the 48-hour mark that Elaine has been missing, we remain very hopeful and focused on locating her," said San Mateo County Sheriff's spokesperson Gretchen Spiker.

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Spiker says the search footprint is expanding to include areas west of the preserve beyond Skyline Boulevard. So far, a 12-mile area has been searched with no sign of McKinley.

"We have more than 150 search and rescue volunteers here," Spiker said.

The volunteers included a mounted horse patrol from San Joaquin County.

McKinley is described as an experienced hiker. She was last seen wearing a red jacket and black pants when she went missing Thursday afternoon, during a hike celebrating her partner Kit Durgin's Birthday. But McKinley got ahead of the group on Lost Trail.

"Elaine took off like an energizer bunny. I can't eat. I can't sleep. I cry thinking about what it's like for her," Durgin said.

Local hikers say the 1,400-acre preserve is expansive.

"Yeah, the trails can get twisty. You can get confused in areas. There's a steep part near the creeks," said Stephanie Lucianovic.

The sheriff's department is asking residents with outdoor security cameras to review footage beginning Thursday for any sign McKinley, and to let the department know what they find.

"Both the info of sightings, or lack thereof, is very hopeful as we continue to search and retrace Elaine's steps," Spiker said.

The search is set to resume on Sunday morning, if needed.