The woman who died trying to warn motorists of an accident on State Highway 1 has been described as "a lovely lady with ha heart of gold."

Medelina Muir, 61, of Kaiwaka, died yesterday when she was hit shortly after 6pm by a motorcycle at the Pohuehue Viaduct, just north of Orewa.

The car in front of her was involved in a minor nose to tail accident - the driver was known to Muir and she stopped to go and help.

"At this stage it appears she crossed the road to warn on-coming traffic, but was struck by a motorcycle that came around the corner," a police spokeswoman said.

"Sadly she was not able to be revived and died at the scene."

Muir's nephew took to Facebook to pay tribute to her.

"Your kindness will be forever missed. Keep watching over us."

Another family member wrote that Muir had "a heart of gold and was a lovely lady.

"Let us remember the special things about her at this time and treasure the memories she has left behind."

It is understood that family members witnessed the accident.

The Waitemata Police Serious Crash Unit is investigating and it is not yet known whether any charges will be laid.

The driver of the motorbike will be spoken to through the course of the serious crash enquiry, which will take several weeks.

Muir's family have asked for privacy.

They are being supported by Police and Victim Support.