The city of Christchurch and several other districts on New Zealand’s South Island have declared a state of emergency after being hit by the remnants of Cyclone Gita.

Dozens of schools have been shut and roads closed in the South Island as the storm made landfall on Tuesday.

Air New Zealand has cancelled all flights in and out of the capital, Wellington, in the North Island.

Residents were told to expect floods and winds of up to 150km/h (90mph).

The Grey District, Buller District and Nelson Tasman are among the regions in the South Island to have declared a state of emergency, as has Taranaki in the North Island.

“The full impact of the storm will be felt overnight and tomorrow morning,” said Christchurch Mayor Lianne Dalziel.

She urged residents in low-lying areas to evacuate, saying: “We are expecting homes to be flooded.”