The fronts will bring showers up the west coasts of both the North and South Islands today.
Out east it will be mostly fine, with just the odd shower.
There are no watches or warnings in place for severe weather, however there is a moderate risk of thunderstorms in Buller and Westland.
"It is to do with the showers this morning. Some of them have been heavy in that part of the country."
MetService had issued road snowfall warnings overnight for the Lindis Pass, Crown Range Rd and Milford Rd.
"There would have been snow overnight in parts of the South Island," Dyason said.
The forecast was for snow down to 700-800m in Central Otago and the Far South.
"So some of the ranges and higher alpine passes down there would have seen snow. The Crown Range [near Queenstown] I expect would have had a bit of a dusting."
At 5.30am Tekapo was sitting at 0C and Mt Cook Airport 1C.
"It is a cool morning in parts of the South Island."
Tomorrow a ridge moves in from the Tasman Sea, bringing mostly settled weather.
"Showers over the North Island should clear, with just bit of cloud and westerlies.
"In the South Island there will be a few showers in the west and mostly fine weather in the east.
Eastern areas will be the places to be, with mostly fine weather and warm northwesterlies forecast. Gisborne and Napier are in for temperatures in the early 20s over the next few days.
Late Thursday and during Friday, a trough sweeps across the South Island from the Tasman Sea, preceded by a strong west to northwest flow and followed by southwesterlies.
For a time late Thursday and early Friday, west to northwesterly winds may reach severe gale over Fiordland, Southland and Clutha.
This weather trend looks to continue into the weekend, Dyason said.
"There might be a weak front over the weekend, but it won't bring a lot of rain."
On Saturday, the trough weakens as it moves northeast across the North Island and eventually away to the north.
On Sunday, the southwest flow across New Zealand eases as a ridge of high pressure spreads over the country from the west.
Today's weather
• Whangarei
Long fine spells, but a few morning showers, chance heavy. Southwest easing evening. 20C high, 11C overnight.
• Auckland
Showers, possibly heavy, becoming isolated by afternoon then long sunny spells. Gusty southwest easing evening. 19C high, 13C overnight.
• Hamilton
Morning showers then fine spells. Gusty southwest easing evening. 17C high, 7C overnight.
• Tauranga
A few morning showers, then sunny spells. Gusty westerlies easing evening. 20C high, 9C overnight.
• New Plymouth
Occasional showers, easing by evening. Strong southwest, easing evening. 17C high, 11C overnight.
• Napier
Mainly fine, but one or two afternoon showers as gusty northwesterly tends southwest. 19C high, 8C overnight.
• Wellington
Mainly fine with northwesterlies, but a few showers with afternoon southerly. 16C high, 8C overnight.
• Nelson
Chance early shower, then fine spells. Southwesterlies. 16C high, 7C overnight.
• Christchurch
Mainly fine, chance morning shower. Southwesterlies. 15C high, 4C overnight.
• Dunedin
A fine start, then cloud increasing from afternoon and the chance of a shower. Southwesterlies. 13C high, 9C overnight.
