"All seemed good in the night, there was rain overnight but it didn't seem to be causing any trouble and then suddenly a flood came down through the middle of Opunake."
Mr Dunlop was out visiting those affected by the "traumatic event"
"It's just really surprising the sheer volume of water," he said.
"A number of residents have been affected with water through their houses, so it is a traumatic event."
Flooding in Opunake. Photo / Supplied via Facebook
Met Service Meteorologist Rob Kerr said the nearest weather station to Opunake, at Cape Egmont, recorded 105mm of rain overnight, with 23.4mm recorded in the hour until 6am.
Wild weather across the city saw a home on Godden Crescent evacuated at 4.30am. Photo / Brad Ambrose
Family evacuated after weather bomb
Meanwhile, a house was evacuated in Orakei after a bank collapsed, and trees were felled by strong winds in Auckland overnight.
Wild weather across the city saw a home on Godden Crescent evacuated at 4.30am, after a bank behind it collapsed amid heavy rainfall overnight.
A fire service spokesman said the house was being renovated, but a person was living in it at the time.
He also said a number of trees were felled by strong wind overnight.
Weather Watch forecaster Philip Duncan said downpours in Auckland city last night were heavy, and quite a few people said they were woken up by intense rains and wind gusts overnight.