Most of coastal Papamoa and Mount Maunganui slept through the November 14 earthquake and tsunami warnings - but thousands across the Coromandel Peninsula were evacuating their homes.
Thames Coromandel District Council area manager for Whangamata, Tairua and Pauanui Garry Towler said he sounded the sirens at 1.45am on Monday.
Mr Towler said locals could not rely entirely on the sirens.
"A number of communities still didn't have sirens and houses have double glazing, or people simply did not hear the siren or had hearing impediments."
If people felt an earthquake of more than a minute or were knocked off their feet they should self evacuate, he said.
"People should not rely on Civil Defence staff to save their lives."
People should also check the Red Cross phone app, listen to the radio or television and check social media for warnings and what to do.
"If you hear a siren you should seek further advice before you evacuate, find out what is going on."
Traffic at Whangamata heading for the hills after a tsunami siren. Photo/Lesley Staniland
Whangamata resident Jan Findlay said she thought she was dreaming when she heard the siren go off.
"I flew out of bed and put some warm clothes on, I grabbed some vitals in a box and took off in my car.
"I was pretty motivated to move. I grabbed a picture of my father when he was a child but nothing else. I didn't bother with food. I knew I could go three days without it."
