Temperatures are starting to dive as the polar blast touches down in New Zealand.
An enormous cold air mass straight off the Antarctic ice shelf is now hitting parts of the South Island with snow expected down to 100m in southernmost regions.
Forecasters say the cold front will sweep northwards up the country during Monday, opening the freezer door to all of New Zealand.
According to MetService, Rotorua residents can expect a low of -1C tomorrow and a high of just 9C. The forecast is for some morning cloud, then fine with southwesterlies.
Tomorrow's forecast for Tauranga shows a high 12C and a low of 2C. There will be some early morning cloud, then fine. Southwesterlies, gusty in the morning and afternoon.
Taupō's forecasted low for tomorrow is -1C, with a high of 7C. It will be mostly cloudy with some showers in the afternoon.
MetService has issued a road snowfall warning for Desert Rd.
Snow showers are forecast about higher parts of the road from 6pm today until about 7am tomorrow, and up to 1cm of snow may settle near the summit of the road during this time.
Then significant snow is expected from late Tuesday morning until Tuesday evening. In the six hours between 11am and 5pm Tuesday, expect 5-10cm of snow to settle on the road, mainly about southern parts of the road.
Meanwhile, the South Island is feeling the full brunt of the polar blast today.
Niwa Weather says there is even the likelihood those in the south will see temperatures plummet to an icy -20C thanks to a "brutal" wind chill adding an icy sting during this week's polar blast.
MetService is warning the severe gales bringing bitterly cold conditions across much of the South Island will cause stress to livestock, and thick settling snow expected to make driving hazardous.
Cold sleety rain is starting to fall in southern regions with heavy snow forecast to fall in Southland and Central Otago.
MetService has issued a swathe of storm warnings affecting most of the South Island, and eastern regions of the North Island. There are also a number of strong wind warnings being issued across the North Island including the Desert Rd, Hawke's Bay and Manawatu for those driving high-sided vehicles or motorcycles to take extra care.
Road snowfall warnings are now in effect on all alpine passes with up to 8cm of snow expected to fall on worst affected areas.
A warning comes into effect for the Dunedin to Waitati highway in Otago after lunch.
A heavy swell warning has also been issued for Wellington's coastline with 6m swells expected to batter the southern coast from Tuesday morning through to Thursday.