A period of significant snowfall was expected about and above 500m about the Kaikoura Ranges, the Canterbury High Country and foothills and also northern parts of Central Otago.
A heavy snow warning (orange) is also in force in these areas.
The heavy snow watches remain in place for Central Otago, the Southern Lakes and inland parts of Clutha and Southland.
MetService says heavy snow may disrupt travel in affected areas and could damage trees and powerlines. Cold conditions may cause stress for livestock.
ROAD CLOSURES:
Motorists are being warned of closures or disruptions to several roads because of bad weather conditions.
Route 70 Inland Kaikōura Rd (Kaikōura tō Lyford) is closed due to heavy snow. Another update is expected at midday.
SH7 Hanmer Turnoff to Springs Junction - Lewis Pass - is also closed off because of snow. An update on that situation is expected at midday as well.
SH73 Springfield to Arthurs Pass had been closed due to heavy snow also. Motorists in this area are being told that there is no detour available.
"Avoid the area or delay your journey if possible,'' the NZTA said.
It's not all bad news for those wanting to hit the slopes, however.
The Cardrona Alpine Resort in the Southern Lakes district posted a notice on their Twitter page: "Here we go team, fresh snow alert - 23cm of new snow has fallen all over the mountain with some massive wind drifts to play in!
Aucklanders can expect a few showers this morning - and then more frequently from lunch time. A high of 13C is forecast and an overnight low of 6C.
There is also a possibility of squally thunderstorms and hail in the City of Sails as well as strong northwest winds changing into southwesterly winds this evening.
There are a few showers in store for Hamilton and a high of 12C. It will be a chilly night there tonight, with an overnight low of 1C forecast.
Those in Tauranga have a bit of reprieve with fine spells expected. However, showers are forecast by this afternoon and may turn into heavy rain with hail. That will clear by tonight.
Wellington is in for a wet Wednesday, with showers turning to rain by midday, with thunderstorms and hail possible. A high of 11C is forecast in the capital and an overnight low of 5C.
A cold southerly change was expected to spread across the South Island overnight and will bring snow down to 200 to 300m in some places today.
People in Nelson can expect occasional rain that will clear by this afternoon before becoming fine. A high of 10C is expected a chilly 1C low overnight.
Queenstown is in for a partly cloudy day but the forecast includes a chance of a few showers or snow flurries. Southerly winds are also expected.
Invercargill gets showers and southerly winds also and there is a high of 8C in the city today and an overnight low of 5C.