It's been more than a month since Samantha Sayers went missing while hiking in the Vesper Mountains in Washington.

An experienced hiker, Sayers set out on a hike on Aug. 1, 2018, planning to summit Vesper Peak in Washington's North Cascades, a route she had taken before.

The morning of the hike, Samantha said goodbye to her boyfriend Kevin and left for the trail. Kevin said that after Samantha left the house, he texted her to remind her to be careful.

“The last text I sent her that morning was me saying ‘I know you don’t need me to tell you this, but the terrain can be dangerous.’ And she just replied something like, ‘I know. I love you’,” Kevin told NBC's Dateline. He added that he was “110% sure he’d see her that night.”

Samantha’s mother Lisa told Dateline it only would have taken a couple of hours for Samantha to make the descent from the summit to her car. If she was at the summit at 3:00 p.m., Lisa said, she should have made it back to her car by 6:00 p.m. as she said she would.

But Samantha never made it back to her car. Her boyfriend, sitting at home waiting for Samantha’s call, grew concerned.

“By 7:00 or 7:15 p.m., I was on the road. The reason I jumped to it so quick, is because she is prepared. She sticks to her timeline,” Kevin told Dateline. He says he drove to the trail after picking up a cheap flashlight at a nearby gas station.

“I hit the mountain around 10:00 p.m. I didn’t have any gear with me: It was a sad state of affairs,” Kevin said, adding that his flashlight broke a few hours later. He called 911 to report Samantha missing around 1:00 a.m.

After more than three weeks of constantly looking for Samantha, authorities suspended search operations on August 23. The Snohomish County Sheriff’s Office reports that in those three weeks, search operations included 357 hours for air operations, 105 hours for drone operations, 82 hours for the Marine Unit to support search teams going into the search area from Spada Lake and 329 hours for Sheriff’s Office SAR personnel.

"We have exhausted all leads and tips. We've interviewed all witnesses who have come forward. We have checked and double-checked the possible routes we believe Sam could have taken," Search and Rescue Sgt. John Adams said in a press release. "If there was a place we thought she could get to, we put people there to look for Sam, often putting our volunteers and personnel at great risk due to the rugged, remote, and dangerous terrain."

Check out more from Dateline NBC here.

Sayers is from Pennsylvania, but her grandparents live on Harsen's Island. Her grandparents, along with neighbors, are starting a yellow ribbon campaign and tying ribbons around trees to help keep national interest in the story, in hopes that authorities resume their search.

They believe because of her experience, she could possibly still be alive but injured in a crevasse.

Watch Paula Tutman's story on the effort in the video player above.

The Facebook group #FindSamSayers says she was last seen wearing dark gray pants and a maroon hoodie. She also had two hiking poles, a blue backpack, a beige sun hat and a dark gray wool beanie. Samantha is 5’8” tall, weighs about 125 lbs., has green eyes and is bald due to her Alopecia.

She has a tattoo of a tree on her back and tattoos of stars on the side of her head, designed by her mother Lisa as a symbol of strength. If you have any information on Samantha’s whereabouts, please call the Snohomish County Sheriff’s Office at (425) 388-3393.