Ester Taruvinga, who also goes by the name Amazing Grace, was last seen on April 13.
She has links to the Wortley and Beeston areas of Leeds and it is believed she may be in one of those areas.
Acting Detective Inspector Toby Facey, of Calderdale District Police, said: "Clearly our concerns are growing for Ester and I would appeal to anyone who may have seen her in the last seven days to get in touch with police.
"We believe Ester may be in Leeds and, equally, I would appeal directly to Ester to speak to police to let us know she is okay."
Ester is described as blac and approximately 5ft 3in, with shoulder length wavy hair, brown eyes and a small scar on her chin.
She was last seen wearing a long black leather jacket and white Nike trainers, and was carrying a blue leather handbag.
Anyone with any information on Ester or her whereabouts is asked to contact police via 101.