Weather live: Motorists warned against driving to Kaikōura, with no safe routes

Follow our liveblog above for the latest updates

The Kowhai River has breached its banks causing serious flooding, State Highway 1 is closed between Ward in Marlborough and Waipara in North Canterbury and power is out to homes near in Kaikōura.

Abandoned cars are lining the side of a highway and areas are losing power as the deluge moves up the country.

A red heavy rain warning for Marlborough and Canterbury between Ward and Hanmer and southeast of the Awatere Valley, including the Kaikoura ranges, runs until 6am on Wednesday.

Further north, there is an orange rain warning and watch for Wairarapa.

What where are the road closures in the South Island?

State highway closures remain in place in the central and lower South Island from the current weather event, as further disruption is expected.

The following closures are in place:

State Highway 1 from Ward in Marlborough to Waipara, North Canterbury due to flooding

State Highway 63 from Kawatiri to Howard, West Coast, between State Highway 6 and Howard Valley Road due to fallen trees

New Zealand Transport Agency Waka Kotahi (NZTA) also has multiple road area warnings in place around the central and lower south because of the prevailing winter driving conditions, and road users are being urged to travel with extra care and to drive to the conditions.

MetService is forecasting heavy rain and snow today through inland Canterbury to the top of the South Island. A rare red heavy rain warning is in place for Marlborough and Canterbury between Ward and Hanmer Springs and southeast of the Awatere Valley, including the Kaikoura Range. This red level of warning carries the risk of a threat to life from dangerous river conditions, significant flooding, slips and impassable roads.

Further highway closures may be required today if the weather impacts make it unsafe.

Because of the heavy rainfall and melting snow, there is also a risk of ice build-up in parts of the South Island over the coming days that people should be wary of. Roading crews will be laying grit and anti-ice agents on the highways to assist vehicle traction.

Strong winds remain a threat on the West Coast south of Westport, especially for high-sided vehicles, towing vehicles and motorcycles.

Kaikōura wastewater issues

Kaikōura District Council said parts of its wastewater network have experienced overflow events due to the heavy rainfall.

It said the intense rainfall had resulted in stormwater entering the wastewater system at volumes exceeding its normal capacity, leading to wastewater overflows in some locations.

It said council crews had been actively monitoring the network and are responding to affected areas as conditions allow.

As a precaution, residents are being asked to avoid contact with any floodwater, ponded water, or wastewater-affected areas.