Ryan was last seen in the town at around 5pm yesterday (Thursday).
A police spokesman said: “Ryan’s family are concerned for his welfare and would like to hear from him, or anyone who has seen him, so they know he is okay.”
He is described as a white man, clean shaven, around 5ft 4ins tall, of slim build and with short, brown crew cut hair, wearing red jeans and a red T-shirt.
The photograph at the station shows clothing worn by Ryan prior to boarding a train at Boston.
This train was destined for Nottingham but is is not known which stop Ryan got off at.
Ryan walks with his arms held out at a distinctive angle.
Anyone who has any information regarding Ryan’s whereabouts is asked to contact Lincolnshire Police on 101 quoting incident reference 465 of July 7.
EARLIER: Concern has been expressed for a teenager from Boston who has not been seen since yesterday (Thursday) evening.
Ryan Young, 19, was last seen at 8pm.
He was wearing red tight jeans, red Arsenal T-Shirt and a blue rain jacket.
Ryan is 5ft 4ins tall and is of slim build.
It is believed he may have been heading to Nottingham.
It has been stressed Ryan is not in any trouble and is asked to make contact with his carer so they know he is safe.