Road snowfall warnings have been issued for several South Island highways as a low-pressure system bears down on the country.
Motorists using the alpine passes are being warned of potential travel disruptions if forecast amounts of snow eventuate.
MetService said the system was set to bring heavy rain to many areas from Wednesday, especially northern and central parts of the country.
"Strong winds will follow, with a risk of severe gales for eastern parts of the North Island on Thursday and Friday."
MetService meteorologist John Law said the weather was the result of low pressure pushing rain across from Northland west to the Bay of Plenty, while another front was moving up the country from the South Island - bringing colder air and the risk of snow on Thursday morning.
In an update this afternoon NZ Transport Agency Waka Kotahi said rain was forecast to turn to snow on State Highway 73 between Christchurch and the West Coast tonight, and people should expect 15 to 25cm of snow to accumulate about the summit of Porters Pass tomorrow.
"This amount of snow, if it eventuates, will likely require temporary closures so that it can be cleared."
Also on SH73, 2-6cm of snow is expected at Arthur’s Pass, and 2-5cm is forecast for State Highway 7 at Lewis Pass, and potentially up to 10cm east of Lewis Pass.
Further south, lesser amounts of snow are forecast for the Lindis Pass (SH8), the Milford Road (SH94), and the Crown Range Road.
NZTA said contractors would be monitoring the highways and taking action such as closing roads, or introducing restrictions, where necessary.
In the North Island, many places are under rain warnings today, and ferry operators have warned that disruption is likely due to rough conditions.
Strong winds and large swells, including throughout the Cook Strait, are expected until Saturday.
Interislander and Bluebridge are monitoring the weather, and say trips may have to be delayed or cancelled if conditions worsen.
- Allied Media/RNZ
