It’s reported that at around 8.30pm, on March 13, the woman had been walking along King Street when the man, who was at in a red Mini, shouted to get her attention.
He appeared to masturbate before driving off.
The woman told officers that this was the second time the man had done this to her, following a similar incident on West Street a few months ago.
A police spokesperson said: “Officers have since worked with the woman to produce this e-fit.
“We are also carrying out CCTV enquiries in order to trace the vehicle.
“Do you recognise him?
“If you have any information please report this through our online portal or by calling 101.
“The incident number to quote is 995 of March 13.
“Alternatively, if you prefer not to give your personal details, you can stay anonymous and pass on what you know by contacting the independent charity Crimestoppers.”