"We received reports of about three crashes in the area, too ... so it was to the point where driving was affected and motorists were down to about 50kph," she said.
"It's pretty unusual for the Hauraki area and Coromandel."
MetService said snow showers above elevations of 400m were likely in eastern parts of Taihape and Taupo, and over Hawkes Bay and the southern Gisborne ranges.
The forecasters also warned of an active trough moving slowly north bringing "bitterly cold southerlies" across the central North Island.
MetService expected snow in areas above 600m south of Wairoa, then in the ranges north of Wairoa from later this afternoon.
The weather caused chaos for motorists in the South Island. In Canterbury, heavy snow was falling all over of Banks Peninsula earlier today and local authorities advised against travelling in the area.
Summit Road at the base of the Peninsula was still closed this afternoon between Gebbies Pass and Evans Pass.
"We are putting all our resources into clearing the Summit Roads and the roads to major bays," Christchurch City Council said.
"Snow has closed the highway to Akaroa and also the hilltop to the bays."
Travel was not advisable but if required, should only be undertaken by experienced drivers in 4WD vehicles with chains, the council said.
Snow also affected roads in the inner harbour are and the council advised "extreme caution" in that area today.
Earlier today State Highway 93 was closed between Clinton in Otago and Mataura, Southland.
The road reopened shortly after noon but the New Zealand Transport Agency (NZTA) advised drivers to extra care in the area.
The New Zealand Transport Agency said this morning chains were "essential" for anybody driving between Omarama and Cromwell on State Highway 8. Today's wintry blast didn't just make its presence felt in the South.
Not everyone was complaining about the snow. Near Mt Ruapehu, the landscape was transformed after a dusting of snow overnight.
Chateau Tongariro front of house manager Udey Singh said the winter wonderland was enthralling guests and staff this afternoon.
"It's a nice clear day. I think we got enough, what we needed, last night. I believe it's the biggest dump here since 2008," he said.
"It's perfect - good snow overnight and then a perfect day for skiing and snowboarding. The mountain is open."
Mr Singh said roads in the area were open, in contrast to many alpine passes nationwide closed today after ongoing snowfalls.
Dunedin was also blanketed with the white stuff, and snow disrupted some city bus services.
Children in the city's hill suburbs enjoyed making and throwing snowballs and some suburban streets resembled pistes as kids careered down the slopes on boards. slopes on boards.