A southwesterly airflow lies over the country today, moving around a large high in the Tasman Sea. Most regions are going to have some cloud, showers are about too (mainly for the South Island, especially inland areas).

Northland, Auckland, Waikato & Bay Of Plenty A mix of sun and cloud, chance of an isolated shower. Becoming mostly cloudy for Bay Of Plenty in the afternoon with isolated showers late afternoon / evening, chance of  heavy fall. Southwesterlies for most, northerlies for Bay Of Plenty.
Highs: 18 – 20

Western North Island (including Central North Island)
A mix of sun and cloud, chance of an isolated shower late afternoon / evening mainly inland. Southerlies tend southeast later in the day.
Highs: 12 – 17

Eastern North Island
Partly cloudy, a few showers for Mahia Peninsula and coastal Gisborne clear in the morning. Late afternoon or evening a few isolated showers spread off the ranges. Southerlies pick up in the morning.
Highs: 16 – 18

Wellington
Partly cloudy, chance of a shower, mainly later in the day. Southerly winds.
Highs: 14 – 15

Marlborough & Nelson
Mostly cloudy with a few showers, some may become heavy in the afternoon about inland hills and ranges then easing in the evening. Cloud breaks away from Nelson at night. Light winds tend onshore, southerlies push through later in the day.
Highs: 14 – 15

Canterbury
Mostly cloudy although coastal areas may have some sun, showers develop in the afternoon (especially inland) as southerlies freshen, cloud eventually thickens up about the coast.
Highs: 14 – 17

West Coast
Sunny for Fiordland with southerlies, further north expect partly cloudy skies with a few isolated showers and light winds. Showers may become heavy about the ranges in the afternoon (mainly for Buller) then clearing later in the evening.
Highs: 16 – 19

Southland & Otago
A few showers for Southland and coastal Otago, thinning out in the afternoon with sunny areas increasing, any remaining showers clear in the evening. Central Otago may have morning sun then a few showers in the afternoon, clearing evening. South to southwesterly winds.
Highs: 13 – 17