A state of emergency has been declared in Auckland tonight as torrential rain and flooding hits the city - with warnings that a further deluge is possible.

Fire and Emergency says it is dealing with an estimated 1500 calls for help.

Civil Defence Minister Kieran McAnulty announced the state of emergency on Twitter.

“The Mayor of Auckland has declared a state of emergency. NEMA [National Emergency Management Agency] can now provide additional support and resources from other regions. I’m continuing to receive live updates from NEMA, liaising with Auckland based MPs and updating the Prime Minister as needed,” McAnulty said.

Later, Mayor Wayne Brown announced he had declared a state of local emergency in the Auckland region.

”This declaration reflects the extent of damage, displacement and disruption caused by this evening’s severe weather event and enables emergency services and response agencies to draw on resources, and enact additional powers, to assist affected Aucklanders,” says Mayor Brown.

“The region has experienced widespread damage from flooding and torrential rain, with reports of slips and inundation. Infrastructure and emergency services alike have been overwhelmed by the impacts of the storm. The declaration of state of local emergency comes into force immediately and expires in seven days,” he said.

Prime Minister Chris Hipkins has responded to the flooding and devastation across the City of Sails. 

"I'm pleased an emergency declaration has been made due to flooding in Auckland tonight," he tweeted.

"All relevant govt agencies are working flat out to help in an extraordinary set of circumstances. The emergency response is underway and the Government is ready to assist as needed."

The Prime Minister says the Beehive Bunker is being stood up to help with the emergency response.

It comes as a body has been found in Wairau Valley on Auckland’s North Shore, floodwaters swamp the city’s homes, block motorways and close the international airport.

Police were notified at around 7.25pm after the body was seen by a member of the public, near Target Rd. The Herald understands the body was found in a culvert.

A warning over the rain in the city has been extended to 3am by MetService.