Your weather: Antarctic blast on its way to New Zealand

In this graphic windchill below zero is shown in blue. Image / WeatherWatch

An Antarctic blast is about to hit the country, temperatures will noticeably drop tonight and some parts of the South Island will soon experience windchill around freezing.

A cold front begins to sweep northwards tomorrow allowing air, which originates from the Antarctic Ice Shelf, to affect weather across the country, according to MetService.

WeatherWatch predicts the coldest air will arrive on Monday evening when temperatures will plunge overnight across the South Island and some of the North Island.

The cold air will travel further north on Tuesday overnight.

According to WeatherWatch, coastal parts of Southland and Otago will experience windchill hovering around freezing on Monday afternoon, with -5C possible in the more exposed coastal areas such as Dunedin/Coastal Otago.

Further inland amid higher elevation the windchills intensify, and exposed parts of northern Southland and the hills around Otago will drop to -10C on Monday night.

This is colder than the North Pole is right now, which is in its summer season and experiencing windchill around -6C.

The bitterly cold air around the Southern Alps will see wind chill of -15C to -20C on Monday overnight and into Tuesday morning.

For the southern half of the West Coast the angle of the attacking winds may push some valleys well below zero with windchill.

WeatherWatch reports from Hokitika northwards a somewhat “milder” wind should come off the sea.

The forecaster warns livestock even on the West Coast should be protected from the bitterly cold air that may come down from the Southern Alps, especially south of Hokitika.

Monday’s forecast

Whangārei
Cloudy periods and a few showers. Northwesterlies turning southwest in the afternoon. High 17C, low 10C.

Auckland
Cloudy periods and a few showers. Northwesterlies turning fresh southwest in the afternoon. High 17C, low 9C

Hamilton
Mostly cloudy with a few showers. Northwesterlies turning southwest by afternoon. High 16C, low 6C.

Tauranga
Cloudy periods. A shower or two, mainly in the afternoon. Westerlies. High 17C, low 7C.

Whanganui
Cloudy and showery. Strong westerlies. High 15C, low 5C.

Wellington
Partly cloudy. A few showers from afternoon as strong northwesterlies change southwest. High 14C, low 5C.

Christchurch
Morning showers, then fine. However, showers persist about Banks Peninsula, with sleet about high ground. Cold southwesterlies, strong in exposed places. High 12C, low 2C.