Duncan said the weather event won't cause major problems but there may be some alpine issues on highways and up to a few hundred metres of snow flurries in the South Island.
Blustery winds are also expected to accompany the cold temperatures on Friday night and Saturday morning, particularly around the Otago peninsula which could record gusts between 80-110km/h.
On Saturday, the cold weather will track further up the North Island and there would also be more rain across the country.
"Southland your drought problems are very quickly fading and we're hopeful that Waikato will get 40-60mm (of rain) over the next two weeks so that is also some good news," said Duncan.
Later today, rain is expected to sweep across near Mount Taranaki and the Waikato, where farmers are bearing the brunt of a drought.
Tomorrow, it is set to get windy in the South Island as the low-pressure system of the storm moves towards New Zealand.
The southerly is followed by a high-pressure system which means the country's first winter cold snap will be brief and temperatures would warm up again at the end of the weekend.