The coldest week of the year is on the way with a polar blast expected to bring freezing temperatures to the lower North Island and much of the South Island.
MetService is forecasting it to be the coldest week of the year, with freezing temperatures, snow and severe gales expected to hit much of the country.
Georgina Griffiths from the MetService said snow warnings were in place for many roads in the South Island and central North Island.
She said snow could get down to 200m in the south, with large accumulations at higher altitudes.
"And it will feel bitterly cold because it's blowing ... and it's a long-lived southerly so it's got teeth this one."
She said it could cause disruption with many more people on the roads because of the school holidays.
"There's a lot of people trying to move around so that's why we are highlighting this as impactful, a high-impact, severe weather event for New Zealand."
The Transport Agency is warning road users in the South Island to be ready for winter driving conditions from Tuesday.
Journey Manager Lee Wright said drivers would need to check if there were restrictions in place on roads before departing.
Ms Wright said families travelling with children should pack extra provisions and warm clothing in case there were delays along the way.
She also warned drivers using the alternate Picton-to-Christchurch route via the Lewis Pass to allow extra time.
Ms Griffiths said the weather also had the potential to affect Cook Strait ferry sailings.
The coldest temperatures would be in Christchurch and Dunedin which would have highs of 5°C or 6° and would feel like -1° by mid week.
Wellington through to Wairarapa right up to Gisborne and Hawke's Bay is tipped to have rain and bitter cold winds.
But she said all this was great news for the ski fields.