Bus rolls as snow, icy roads and earthquake batter South Island

Snow and ice at Arthurs Point near Queenstown. Photo / Louise Scott

A 6.4 quake, snow and icy chaos - Mother Nature is throwing everything she's got at New Zealand, and North Islanders are next in line.

A polar blast moving up New Zealand reached the North Island overnight, bringing icy conditions, rain and high winds.

As if a freezing cold snap and snow weren't enough, a 6.4 magnitude offshore quake gave Southerners a good shaking about 7pm.

The quake hit 190km southwest of Snares Island, south of Stewart Island.

Thousands of people reported feeling the quake, with descriptions ranging from "rolling" and "swaying" to "rumbling". Some said it lasted up to a minute.

Meanwhile extensive weather warnings have gone out as freezing temperatures start to make their way up the country.

Queenstown was expected to hit -4C overnight, and it was already -1C near Mt Cook before midnight last night, when temperatures were still dropping.

Icy and snow covered roads in Queenstown as an icy winter blast hits the South Island. Photo / James Allan

In Invercargill it was a shivery 0.4C, and the temperature in Christchurch dropped to 1.2C. Snow was forecast to get down to sea level last night in Christchurch and Dunedin.

The snow has already caused problems. A bus rolled on State Highway 6 near Makarora in Otago last night, a police spokeswoman said.

No one was hurt in the crash, which happened just before 6.30pm on the Haast Pass-Makarora Rd about 15km north of the settlement.

About 10 passengers had to sit tight inside the tipped bus and wait to be rescued, as snowy conditions slowed the arrival of the first responders.

Arrowtown is covered in snow as an icy winter blast hits the South Island. Photo / James Allan

Icy and snow covered roads in Queenstown as an icy winter blast hits the South Island. Photo / James Allan

A Fire and Emergency New Zealand spokesman said the first crew on the scene reported no-one was trapped and injuries were "nil or minor".

Contractors were trying to tow the bus, which was blocking the road.

Police also helped get passengers to their destinations, a police spokeswoman said.

The NZ Transport Agency advised that the road was now closed because of snow.

A car also hit the side of a bridge on the Gibbston Highway near Queenstown yesterday after hitting black ice, the spokeswoman said.

Nobody was injured in the crash.