In the days since the discovery, not a single person has reported seeing McBroom.
A wife and mother, McBroom, who went by Kathleen, was supposedly heading for work the Monday morning she vanished. Nobody is quite sure why she was on the highway.
"My very first thought was that she needed some time away, that maybe she was just going to cool off somewhere, but I've got this gut feeling that something bad has happened," said Sue Rissel, 28, a friend of McBroom's who knew her online.
"The more we find out, the more concerned I am, because it's not like her to be gone that long."
In the days before she disappeared, one of McBroom's teenage daughters returned after spending more than a year out of state, and McBroom appeared to be thrilled about the reunion in a personal blog entry dated Oct. 26.
"was sweet to hug my girl again," she wrote. "really nice to have everybody home at home right now. was so strange (good) to have all of us around the dinner table last night. the small and simple things matter more."
But McBroom was also stressing about her job with the U.S. Army Corps of Engineers at Elmendorf Air Force Base, said Bishop Lance Nelson, who supervises McBroom's ward at the Church of Jesus Christof Latter Day Saints.
McBroom had gotten renewed interest in the church in recent years and had taught primary school there, Nelson said. He called her a loving mother and said her abrupt disappearance has shocked those who knew her, especially her family.
"I think they've found it really difficult. They're going through different stages, I think, of grief and concern," Nelson said. "The worst thing is the uncertainty, just not knowing. I think that's been pretty hard on them."
The last morning anyone saw McBroom, she had shoes for walking rather than working, Rissel said.
Then, at about 8:30 a.m. Oct. 31, an Alaska State Trooper responding to a report of a possible drunken driver whose pickup was swerving erratically on the Seward Highway talked to McBroom while she was stopped in a pullout, troopers spokeswoman Megan Peters said. After testing her sobriety and running her on a database, the trooper left her with a suggestion she take a nap.
"She pulled over because she was tired. There's no signs of any kind of intoxication, nothing was in the system to make us want to hold on to her longer," Peters said. "There was no reason for us to keep her."
It wasn't until that evening, when McBroom didn't return from work, that her family began calling her cell phone. She was reported missing the next day.
After her truck was discovered, more than 20 searchers, police officers, troopers and railroad personnel mounted an expansive search that lasted until dark, said police Lt. Dave Parker.
A trooper helicopter peered down between the trees on the cliff tops and scoured the coastline for any sign of McBroom. The Alaska Railroad brought a truck equipped to ride on tracks so searchers could cover more ground as they peeked into crevices in the shoreline rock, Parker said.
At the end of the day, the only clues they had were what they started with: the truck and the belongings inside, which included her cell phone.
Police are now left to wonder if McBroom's pickup was moved after the trooper talked to her -- a possible sign of foul play -- or if she simply ditched it and hitched a ride. Or, given the proximity of the embankment, did McBroom jump or fall into the frigid water below, surging with tides up to 30 feet that day?
"If she had ended up in the water, she'd be gone. There's just no way around it. She would have been swept away," Parker said. "But if she had hitchhiked or gone someplace or gotten picked up -- it's a busy highway. That's always the potential, but as I understand it, we haven't gotten any leads from people who have seen her."
The pickup has been brought back to Anchorage to be examined for evidence, but there are no immediate plans to continue an active search for McBroom. Police instead are hoping she will either turn up or they will get a tip that points them in the right direction, Parker said.
McBroom's church has put fliers out, sent members to the area where the truck was found and offered to send volunteers to help police with any search effort that becomes necessary, Nelson said. Police, however, have not offered any concrete ways the church members can help, he said.
"I am assuming right now that she isn't alive just because if she was out there somewhere lost, then there's no way at this point, because there haven't been people looking for her," said
Lena Morgan, an online friend of McBroom's living near Dallas. "I can't imagine her doing any harm to herself, and I just wish that more attention had been given in the beginning."
McBroom is described as 5 feet 5 inches tall, 200 pounds, with brown hair and blue eyes. She was wearing a white, hooded jacket.