Weather: Wet conditions on the way for most of New Zealand, possible snow in some areas

New Zealanders should make the most of the dry on Tuesday as wet and snowy weather is forecast for the rest of the week.

WeatherWatch is forecasting a cloudy, dry day for most of the country on Tuesday - with showers for the upper North Island, East Cape, Gisborne, South Westland and Southland.

However, heavy rain is on its way.

Heavy rain is forecast for northern and western parts of the South Island from Wednesday to Thursday, with the heaviest falls expected about the ranges of Kahurangi National Park and Buller, MetService reported.

An orange heavy rain warning has been issued for Buller, including Kahurangi National Park and Takaka Hill from 7pm Wednesday until Thursday afternoon.

MetService has also issued a heavy rain watch for the ranges of Westland south of Hokitika from Wednesday until Thursday morning and for Richmond and the Bryant Ranges including the Rai River Valley from 9pm Wednesday until Thursday afternoon.

Rain is also expected to develop for most of the South Island on Thursday and possible snow down to 400 metres in the far south on Thursday evening and in Canterbury on Friday.

The North Island is mainly fine on Wednesday with isolated showers in Bay of Plenty to Taupō. Occasional rain is expected to develop on Thursday.

Rain in the north and east is forecast for Friday, with scattered showers elsewhere in the North Island.