Maryann Miller, whose stepson Joshua has been missing in St. John's since early Friday morning, says she's concerned for his welfare.
Miller says she was notified Joshua was missing on Sunday.
"I just don't want nothing to happen to my son," Miller told CBC News.
Police told Miller the last time anyone saw Joshua, he was near Stavanger Drive.
"Cops told me he was last seen on the street [in the Stavanger Drive area] and he jumped over a fence from the cab," said Miller.
Police are releasing few details about how Miller went missing in the early hours of Friday morning.
"The exact circumstances of his disappearance, we are not giving the full details at this time. He was seen possibly getting out of a cab in that area," said RNC Const. Talia Murphy.
Maryann Miller still has hope that Joshua will be safely found.
"I just hope he's not in the woods somewhere, with all this snow, and the snowstorms. I just hope that he's okay and he's at somebody's house and he calls me," Miller said tearfully.
Miller said the last time she saw him was at a family funeral, in the fall of 2011.
Police have suspended the ground search for Tuesday, due to darkness.
Earlier Tuesday, an intensive search was underway in a wooded area off Stavanger Drive in St. John's.
Miller, 20, was last seen in the area Friday morning, wearing dark pants and a t-shirt.
Police have said every available resource is being put into the search.
"Our RNC K-9 unit, the mounted unit, Rovers Search and Rescue, members from [the] criminal investigation division and also patrol services members are actively searching for missing person Joshua Miller," said Murphy.
A Universal helicopter, secured by provincial Fire and Emergency Services, was also engaged in the search.
"We are concerned for his safety and well-being; it has been quite cold the last few nights. Temperatures approximately -20. We have had a snow storm and, given the attire he was wearing at the time of his disappearance, we are concerned for his safety," said Murphy.
Miller is six feet one inch tall and weighs about 180 pounds, with blue eyes and short, sandy hair.