Snow and ice in the South Island has closed highways as the cold weather system moves north, rain is hitting the lower North Island and fog at Auckland Airport is expected to cause delays.

The cold south to southeasterly weather system is bringing more snow to Canterbury and Marlborough, and MetService warns severe south to southeast gales are possible for parts of the South Island.

Snow and ice closed State Highway 1 south of Kaikōura at Hundalee, and no detour is available.

Further south, SH8 Tarras to Omarama and SH85 Kyeburn to Alexandra are closed, and motorists should take alternative routes.

In Auckland, heavy fog that blanketed Auckland last week has returned to cause another morning of disruptions.

Auckland Airport says delays and cancellations are expected throughout the morning.

Ferry services to and from Auckland CBD were also likely to be delayed due to heavy fog, Auckland Transport says.

The airport's live flight tracker showed a number of flights in and out of the city had been cancelled.

These included flights from Tauranga, Nelson, Palmerston North and New Plymouth.

The weather system is bringing rain to the lower North Island, with with some heavy falls expected in the eastern hills of Wellington and the hills and ranges of Wairarapa.

-RNZ.