The warm mostly sunny weather of the weekend is now over as rain begins to settle in around most parts of the country this morning.
Some areas, including Dunedin, won't see temperatures get double digits as another cold southwesterly change hits Southland and Otago bringing snow to as low as 300m.
Heavy rain has already slammed the West Coast, with between 140mm and 180mm recorded around the glaciers.
MetService duty forecaster Peter Little said there would be a risk of thunderstorms to other western parts of the country, including the North Island, as the front settles in.
While it will get wet and wild, the cooler temperatures won't hit the North Island until Tuesday as the front slowly moves up New Zealand.
Little said most of the North Island, including Northland, Auckland, Waikato, Taranaki and Bay of Plenty, would already be experiencing rain this morning, with heavy falls expected, before it lightens this afternoon.
Temperatures will be relatively mild. Auckland and Tauranga will both get to 18C today, but cool down to a high of 14C tomorrow.
Hamilton will settle on 17C today before lowering to 13C on Tuesday.
Wellington has been living up to its windy reputation, having already clocked up 104km/h in the Kelburn ranges. While it wasn't too cold at the moment - a high of 15C expected - the rain will move in this afternoon.
Christchurch was also managing to remain mild and currently sitting on 16.9C, Little said. A high of 18C was expected before the front hits this afternoon plunging temperatures to 11C by 4pm.
However, Dunedin had already hit its high of 12C before most people got out of bed. It was currently 8C and raining and Little doubted it would get much warmer.
Snow is expected in both Southland and Otago and there were currently road snowfall warnings on the Crown Range Rd near Queenstown, while the Milford Rd was closed due to avalanche concerns.
State Highway 6, between Ross and Franz Josef, is also currently closed due to flooding.
Conditions are expected to ease later in the week but Little said the weather would remain changeable, typical for Spring.
"It's going to be one of those weeks, people will need to keep a jacket handy."
Philip Duncan of Weatherwatch.co.nz said a second cold front lands on Wednesday, followed by a third cold change on Saturday for the South Island and the lower North Island.
He told people to expect a fluctuation in temperatures as the fronts arrive and leave the country, while northern New Zealand wouldn't be as affected by the bitter cold for too long.