An intense cold outbreak is expected to affect the country on Wednesday and Thursday.

"Strong winds and bitterly cold temperatures may bring stress to livestock," says a MetService spokesperson.

"Also be aware that unseasonable frosts may affect crops in many areas."

While widespread warning amounts of snow are unlikely there is a high probability that many South Island roads will be affected by snow and some roads over the lower and central North Island.

People are advised to proceed with care and keep up to date with the latest MetService forecasts and advice from Waka Kotahi NZTA.

"On Wednesday there is a low confidence that snow accumulations will reach warning amounts for the south of Fiordland, Southland, Clutha and Dunedin.

"There is a low confidence of severe southwesterly gales for the Banks Peninsula, Wellington and the far south of Wairarapa late Wednesday and during Thursday.

"On Thursday, there is a low confidence in severe southwesterly gales along the east coast of Wairarapa and for coastal Hawke's Bay and Gisborne."