Three domestic flights have been cancelled.
A foggy morning has greeted many Kiwis today and a warning of wet weather is on the horizon.
Areas in Taupo, Wairarapa, Waikato and Auckland are shrouded in fog.
"A really messy low" will creep over the country today and tomorrow, bringing heavy rain, MetService meteorologist Sarah Haddon said.
Rugby fans were warned to dress for wet weather ahead of the Lions game against the All Blacks in Wellington tomorrow night.
Last night's temperatures dipped to -4C in Waiouru and the Desert Rd. Dunedin got down to -3C, Christchurch 2C, Auckland 5C and Wellington 8C.
A heavy rain warning is in place for Westland and Buller where up to 160mm could accumulate.
"This amount of rain will cause rivers and streams to rise rapidly, and may lead to slips and surface flooding," MetService warned.
A severe weather watch is in place for Nelson, Fiordland, Canterbury High Country and the Southern Lakes.
Haddon said the main band of rain would move off the country by Monday evening but showers and southerlies would remain.
"As it leaves to the east it will bring southerlies behind it with showery weather.
"Different areas of the country will have different periods where it eases."
Metservice meteorologist John Law encouraged people to keep a lookout for weather warnings.
"Of course, it's the rugby Saturday night here in Wellington," Law said, noting those attending the Lions and All Blacks game would be battling the weather.
There was a rough prediction of 10-20mm of heavy rain for Saturday, and overall 15-30mm for the weekend. Game day was also expected to be a typical windy Wellington day, with winds of 40-50km/h are predicted.
Saturday would have a high of 13C and a low of 10C for the capital, and Sunday would bring a predicted low of 8C.
Auckland could expect 15-25mm of rain, mainly on Saturday afternoon, and a further 5-10mm overnight. Sunday would only bring showers.
Temperatures will be mild: 16C was expected on Saturday and a low of 11C, and Sunday would bring a low of 10C.
