Police Scotland have issued an appeal for anyone who may have seen Shaun Sweeney, from Berwick, as it was “very unusual” for him to be out of touch.
The 19-year-old travelled to Coatbridge to spend the night with friends on Thursday, but when they got out up in the morning he had vanished.
He was last seen in the Kirkwood area of Coatbridge at around 10.30am on Friday.
Inspector Claire McGuckien said: “Our concern for Shaun is growing. He is here visiting friends and it’s very unusual for him to just go off and not be in touch with them.
“I am appealing for anyone who may have seen Shaun, he would have been quite distinctive as he was wearing a heavy Parka jacket in this warm weather.
“His family and friends are understandably distressed at his disappearance and just want him back safe and well.”
Shaun is white, around 6ft tall, with a slim build, short brown hair and a dimple on his chin.
He was wearing a green Parka-style jacket with a fur hood, a black T-shirt, grey jeans and black Adidas trainers.
The teenager has family in Berwick and in Glasgow.
Officers have been speaking to relatives and friends for any information on where he may have gone.
Police Scotland said it was “completely out of character” for him to go off and not be in touch with his friends and “they are extremely concerned about him”.
Anyone with information has been urged to contact officers at Coatbridge Police Station via 101 requesting the Coatbridge sergeant.
Meanwhile, a woman has been reported missing having last been seen near to Queen Street train station heading in the direction of Buchanan Street in Glasgow at about 5.30am on Friday.
Emma Johnstone, 23, of Strathaven, South Lanarkshire, was on a night-out with friends and family but left the group at that time and has not been in contact since.
She is described as being 4ft 10ins, slim and with dark brown, long hair and brown eyes. When last seen, she was wearing a red crushed velvet jumpsuit with long sleeves and had bare feet.
Sergeant Paul Doyle, of East Kilbride police office, said: “As time passes, we have growing concern for Emma, who has not been seen since the early hours of the morning. This is out of character for her.
“When she left her friends, she had no shoes with her and is not believed to have any money or a mobile phone with her.”
Officers have urged anyone with information to contact police via 101, quoting incident number 0460 of Friday.