The search continued Saturday for a woman who went missing on Thursday during a hike in the hills above San Mateo County.  

More than 150 trained rescue personnel are fanning out over a search area that has now been expanded.

Margaret McKinley, known to her friends as Elaine, joined a small group for a hike on Thursday morning in the San Mateo County open space known as the Windy Hill Preserve.

“They started at around 10:00 in the morning, and Elaine, in their hike, got ahead of them,” said San Mateo Sheriff PIO Gretchen Spiker. “And so those who were hiking with Elaine — her loved ones — lost sight of her.  And by the time they caught up to the area where they thought she would be, she was not there.”

Her friends immediately reported Elaine missing and a search operation began quickly but without success. By Friday, the search had grown, including volunteers on the ground as well as drones and aircraft overhead, one employing heat sensing technology.

McKinley is 79 years old, and though she is strong and active, she is also said to have some dementia brought on by Alzheimer’s Disease. It’s possible she became confused and began wandering, so officials are asking people who live on the boundaries of the open space to review any surveillance or doorbell camera footage they may have, reaching back to 10 a.m. Thursday.

“If they spot Elaine on their cameras, or if they don’t,” said Spiker.  “Both the information of sightings or lack thereof is very helpful as we continue this search because it can guide us to retrace Elaine’s steps.”

On Saturday morning, Martha Angell and Catherine Flanagan were hiking in the hills and spotted a number of the more than 150 volunteers involved in the search effort.

“There were a lot of search people in yellow vests with dogs, searching and going through the brush, and on and off the trails,” said Angell. “So, it seems like an enormous effort is being put into this.”  

“I typically go up the hill, up Windy Hill, to the top and back down,” said Flanagan. “And if you do that, it’s pretty much a straight shot all the way to the top and then back. But there are trails that go off from that, especially once you get to the top, there’s a network that goes on the other side of the hill.”

She went missing on a route called Lost Trail, near Skyline Boulevard, and the Sheriff’s Office has now expanded the search to the area west of that road. And while each passing hour makes survival less likely, no one is giving up hope yet.

“In San Mateo County, our Search and Rescue volunteers have been involved in successful search and rescue operations in other counties with individuals who have been missing for days, even,” said Spiker. “So, as we hit the 48 hour mark that Elaine has been missing, we remain very hopeful and focused on locating her.”

Saturday’s San Mateo County search effort included help from eight neighboring counties: Alameda, Contra Costa, Marin, Napa, Santa Clara, Santa Cruz, San Joaquin, and Sonoma. They said she was wearing black pants and a red jacket, and anyone with a sighting or information is asked to call 911.

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