Shelby Wilson was last seen walking Westminster Road at around 3.30pm yesterday (March 24).
The 13-year-old is described as 5ft tall, of slim build, with blonde straight hair. She reportedly speaks with a slight Scottish accent.
Shelby was last seen wearing a black jumper and grey joggers.
Police said she has links to Lancaster as well as Morecambe.
PC Emma Walker, of Lancashire Police, said: "We are concerned for Shelby’s health and well-being and would urge members of the public to help us with any sightings of her.
"Likewise, if you are reading this Shelby then please get in touch with us."
Anyone with information can contact police on 101 or 01524 596920, quoting log number 1720 of March 24.
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