New Zealand weather maps reveal intensity of 'spring blast' coming our way this week

New weather maps show just how wet, cold and windy a "classic spring blast" heading our way will make New Zealand over the coming days.

On Tuesday, WeatherWatch warned New Zealand was about to feel the brunt of "two surges of severe gales" along with a cold snap, heavy rain and snowfall.

Now, forecasters have released a series of maps and graphics showing just how intense the weather is likely to get across the country this week.

Wind

The stormy weather kicks off with gale-force winds on Wednesday, which WeatherWatch graphics show will be above 90km/h for most of the Auckland region.

New Zealand weather maps reveal intensity of 'spring blast' coming our way this week
Photo credit: WeatherWatch

"Gales on Wednesday will mainly impact the western North Island and Auckland with gusts of 70-100km/h and some isolated locations in the west," WeatherWatch says.

More exposed areas, like the Manukau Heads and Kaipara Harbour, may see gusts between 110 and 140km/h for a time on Tuesday afternoon.

New Zealand weather maps reveal intensity of 'spring blast' coming our way this week
Photo credit: WeatherWatch

Another surge of blustery wind is anticipated on Friday further down the country, mostly impacting the upper South Island and lower North Island.

"These winds may be stronger than Wednesday's as they get funnelled through the Cook Strait area. Gusts on the tops of the ranges may exceed 160km/h with 130km/h gusts lower down."

New Zealand weather maps reveal intensity of 'spring blast' coming our way this week
Photo credit: WeatherWatch

MetService warns the wind will bring "dangerous coastal conditions" along the west coasts of both islands on Wednesday and Thursday.

"Very long period southwesterly swell and high waves are forecast. These waves carry a lot of energy - extra caution around the coast is recommended."

Rain

It's not just wind Kiwis need to keep an eye out for - it's heavy downpours too.

"The main cold front moves over New Zealand [on Tuesday] bringing rain, then more surges of wet weather move in over the days ahead," WeatherWatch says.

"The bulk of the heavy rain will be on the West Coast while eastern areas look drier."

NIWA Weather says the rain is caused by "ribbons of moisture" flowing thousands of kilometres down toward New Zealand this week.

Snow

In some parts of the country - mostly down south - that rain will actually look more like snow.

"Heavy West Coast rain will turn to heavy snow in the mountains, with over one metre likely to accumulate on the summits over the coming five days," WeatherWatch said on Tuesday.

New Zealand weather maps reveal intensity of 'spring blast' coming our way this week
Photo credit: WeatherWatch

"A few snow flurries - lighter and unlikely to settle - will be expected to low levels in Southland and Otago on Wednesday."

MetService warns snow will be seen as low as 200m in the far south, with road snowfall warnings currently in force for many alpine passes and a watch in place for patches of heavy snow.

Temperature drop

Another MetService graphic shows temperatures are likely to plummet across New Zealand on Wednesday.

And the forecaster has found the culprit - a cold air mass direct from Antarctica.

A temperature map produced by WeatherWatch shows temperatures are likely to be between 4C and 8C colder than normal on Wednesday for most of the South Island and a large portion of the central North Island.

New Zealand weather maps reveal intensity of 'spring blast' coming our way this week
Photo credit: WeatherWatch