Heavy rain, gales and thunderstorms have hit the north, mainly affecting central New Zealand, while parts of the south are blanketed in snow.
Orange warnings are in place for much of the country to see heavy snowfall later today and tomorrow.
Rain is gradually spreading across the North Island. Metservice is forecasting snow will spread across the North Island this evening and into tomorrow.
Metservice says an active line of thunderstorms is passing through the Taranaki region.
Motorists travelling over Auckland's Harbour Bridge today have been urged to take care with big winds forecast to hit the city.
Waka Kotahi asked motorists to take extra care if they were travelling over the harbour bridge - especially those in high-sided vehicles.
The wind warning also applies to southern and eastern Wairarapa including the coastal Tararua District, as well as Wellington and coastal Marlborough north of Ward.
Strong wind watches are in place for Northland about and south of Dargaville, Auckland, Great Barrier Island and the Coromandel Peninsula.
Watches have also been issued for coastal parts of Hawke's Bay and Gisborne about and south of Tolaga Bay, Taranaki and coastal Whanganui, Nelson, Buller, and Westland north of Bruce Bay as well as Hawke's Bay, Kapiti-Horowhenua, the Kaikoura coast and the remainder of Wairarapa.
Orange warnings for heavy snow are in place for Marlborough, south of Seddon, and Canterbury, north of the Rakaia River as well as Taihape and the Tararua and Remutaka ranges, including the Remutaka Hill Rd.
Heavy snow watches are in place for Marlborough about and north of Seddon, Nelson and Buller (200m), as well as the Inland ranges of Hawke's Bay and Gisborne south of the city (500m) and Canterbury about and south of the Rakaia River.
In Canterbury, snow to sea level is possible and is expected to become heavy inland above about 200m.
High avalanche warnings have been issued by the NZ Mountain Safety Council (MSC) as heavy snowfall reaches low levels across the South Island.
The New Zealand Avalanche Advisory danger ratings have risen to "high" for Aoraki/Mt Cook, Two Thumbs, Craigieburn, Nelson Lakes and Tongariro.
Arthur's Pass, Mt Hutt, Taranaki and Ohau have also moved to "considerable" danger.
"As a result of this storm and the conditions, MSC encourages people to stay in bounds at a ski area for the first fine weather day once things clear," a spokesperson said.
"This will allow the snowpack to settle and give avalanche forecasters time to accumulate more data so they can produce new forecasts that incorporate a better picture of what's going on in the backcountry."
Snow is falling on a number of alpine passes and more is on the way, possibly to as low as sea level in some parts. It was sleeting and trying to snow on Christchurch's Port Hills at about 12pm.
The NZTA is desperately trying to keep the Hundalees open this afternoon.
An NZTA spokesperson said it is very snowy on SH1, particularly on the Hundalees, but as it is the only route currently north to south, crews are working hard to keep trucks moving.
Metservice is forecasting a rapidly deepening low will move across central New Zealand from the west today and early tomorrow bringing heavy snow to low levels from Taihape to Canterbury, and possibly severe gale southerlies for central areas.
Snow is blanketing the Crown Range as well as the Porters, Lewis and Burkes passes and is reportedly falling across most of Canterbury above 200-300m.
This video was captured in Methven this morning.
The snow is causing disruption on a number of highways.
SH48 Bruce Rd, Ruapehu is closed due to snow and ice. SH73 Porters Pass is closed to all vehicles. Milford Rd (SH94) is closed between Hollyford Rd (East Gate) and Chasm (West Gate). It is expected to reopen later this morning.
Burkes Pass (SH8) was closed to towing vehicles at about 11.50am. SH8 Lake Pukaki to Fairlie was closed for about two and a half hours but has since reopened.
SH7 Hanmer Turnoff to Springs Junction (Lewis Pass) is closed and an update is expected at 12pm.
This video was taken in Springfield this morning.
• Napier-Taupō Rd - 3cm to 5cm of snow may accumulate near the summit of the road with lesser amounts down to 500m.
• Desert Rd - heavy snow falls from tonight until tomorrow morning. Snow showers are expected to continue through to Monday evening. Expect 15cm to 25cm of snow to accumulate on the road.
• Remutaka Hill Rd - heavy snow falls expected from this evening until tomorrow morning. Expect 15cm to 25 cm of snow to accumulate above about 400m, with lesser amounts down to 200m.
• Lewis Pass - heavy snow is expected to ease this evening. A few snow showers are expected to continue through to tomorrow morning. Expect 20cm to 30cm of snow to accumulate on the road, especially east of the summit.
• Arthur's Pass - heavy snow is expected to ease this evening. Expect a further 10cm to 20cm of snow to accumulate on the road.
• Porters Pass - heavy snow is expected to ease this evening. Expect a further 15cm to 25cm to accumulate on the road.
• Crown Range Rd - the threat of snow has passed for now. However, a few light snow showers may affect the road during early tomorrow morning and 1cm to 2cm of snow may settle on the road.
• Milford Rd - snow showers have now cleared. However, a few light snow showers are expected to return early tomorow morning.
• Dunedin to Waitati Highway - a few snow showers are expected to affect the road tomorrow morning and 1cm to 2cm of snow may settle near the summit and lesser amounts down to 300m.
OPINION: New Zealander reflects on delivering speech at St James' Palace.