Not a lot is going on in New Zealand weather wise for most of today, conditions will deteriorate later on however as a low in the Tasman Sea moves towards the western side of the country. This low combines with a cold southerly airflow which moves onto the South Island overnight.

Northland, Auckland, Waikato & Bay Of Plenty
Sunny spells with westerly winds, a few showers for a time especially this afternoon. Bay Of Plenty may not see showers till more towards evening. Rain moves in overnight.
Highs: 22-24

Western North Island (including Central North Island)
Mostly cloudy with the odd shower, rain develops overnight. West to northwesterly winds pick up at night.
Highs: 15-20

Eastern North Island
Cloudy areas push into the Wairarapa this morning bringing the chance of a light shower, drier further north with some high cloud and westerly winds.
Highs: 17-24

Wellington
Mostly cloudy with the chance of a shower, southerlies tend northerly late afternoon. Overnight rain.
High: 16

Marlborough & Nelson
Cloudy with the odd shower possible, rain develops late afternoon or evening then becomes heavy. Heavy snow may lower overnight to 1000m about southern Marlborough. Light winds pick up from the east or southeast overnight.
Highs: 16-19

Canterbury
Mostly cloudy with the odd shower or drizzle patch, rain from late afternoon or evening, becoming heavy especially about North Canterbury. Snow lowers to 900m overnight for northern parts of North Canterbury, 400m for South Canterbury, snow will be heavy above these levels. South to southeasterly winds.
Highs: 10-12

West Coast
There may be some sun this morning, chance of a shower for North Westland. Cloud thickens from afternoon then rain sets in towards evening, rain may become heavy about Buller. Light winds then east to southeast winds pick up at night. Snow lowering about the mountains of Fiordland to 300m at night, 500m further north.
Highs: 12-15

Southland & Otago
Mostly cloudy with the odd shower, there may be a few light snow flurries to 400m then lowering to 300m at night for Southland. About Otago expect mostly cloudy skies, the odd shower then rain from evening. Snow flurries lowering to 300m overnight. Cold south to southwesterly winds.
Highs: 10-12

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz