Christchurch has been placed under a state of emergency after torrential rain triggered widespread flooding.

The announcement was made by Emergency Management Minister Mark Mitchell, who has travelled to Canterbury this afternoon to survey the damage.

Severe winds gusting up to 150km/h have buffeted Wellington, damaging roofs, downing trees and closing roads.

Fire and Emergency NZ said it attended 93 minor storm-related events between 6am and 2.10pm, and referred a further 66 to other agencies.

Flights have been cancelled at Wellington Airport until at least 6pm.

Monster waves have pounded the coastline, dumping debris on to roads and making driving hazardous.

MetService has upgraded Wellington’s wind warning to a rare red level, with destructive gales and a threat to life from flying items and falling trees.

“Destructive winds will cause widespread damage including powerlines and roofs, with dangerous driving conditions and significant disruption to transport and power supply.”

The warning will last for 13 hours until 3am tomorrow.

“Stay indoors or seek sturdy shelter away from trees. Avoid travel. Be ready for power and communication outages.”

A local State of Emergency has been declared for the Selwyn District.

Follow the latest updates from the wild weather in our blog below.