A warning to North Shore residents to remain vigilant after the second case of a man indecently exposing himself to a young girl.

At 10am a 10-year-old girl was cycling with her friends in Belmont when a man exposed himself to her.

The man was sitting in the font passenger seat of a parked navy-blue car on Seacliffe Avenue, with the door open and his feet on the ground.

Police say he matched the description of a man who exposed himself to another 10-year-girl in Devonport last week.

He's described as a 35 to 40-year-old European man of solid build with tan skin and short, brown, spiky hair.