Update: Melanie has been found safe and well, police said on Thursday afternoon.
Lincolnshire Police are searching for a missing 38-year-old woman from the Horncastle area.
Melanie, whose surname has not been provided, is described as a white female, 5ft 1ins tall with a slim build and short brown hair.
She has small tattoos on both arms as well as her shoulder blade.
Police added that she was last seen wearing blue ripped skinny jeans, a short sleeve top in cream, a thin blue jacket, pink Armani sliders and a JD sports carrier bag.
If you have seen Melanie please call 101 quoting incident 465 of September 1.