Grave fears for lost NSW woman

Searchers have found no sign of Elizabeth O'Pray, 77, who left her Medlow Bath home in the NSW Blue Mountains last Monday morning.

There are grave fears for a woman who has been missing for a week in the NSW Blue Mountains. (AAP)

There are grave fears for an elderly woman who has now been missing for a week from her NSW Blue Mountains home.

Police and the SES have found no sign of Elizabeth O'Pray, 77, who left her Medlow Bath home last Monday morning.

A local resident on Friday night thought he heard a call for help from the valley below Peckman's Plateau but searchers found nothing.

Searchers spoke to Mrs O'Pray on her mobile last Tuesday night when she is believed to have told them she was OK but lost.

The 77-year-old is known to walk along Grand Canyon Road in Medlow Bath and a small track towards Katoomba.