A southerly quarter airflow swings around to the northeast in the afternoon over New Zealand today, a un-organised front over the upper North Island strengthens from afternoon bringing heavy rain potential.

Northland, Auckland, Waikato & Bay Of Plenty
Rain with heavy falls possible from afternoon about Northland and Auckland then towards evening about the Waikato and Bay Of Plenty. Rain may then ease about Northland in the evening. Northerly winds.
Highs: 19-21

Western North Island (including Central North Island)
Mostly cloudy with southeasterly winds developing late morning, rain overnight as the flow tends more easterly.
Highs: 16-19

Eastern North Island
Mostly cloudy with southerly winds freshening in the morning, could be a shower or two with some rain about northern Hawkes Bay and Gisborne during the day. Rain spreads southwards later in the evening / overnight as the airflow tends easterly.
Highs: 18-21

Wellington
Mostly cloudy, may be a shower or two otherwise mainly dry. South to southeasterly winds freshen in the morning.
High: 16

Marlborough & Nelson
Some morning sun then cloud starts to thicken from afternoon, southeasterly winds picking up in the morning.
Highs: 16-18

Canterbury
Morning showers for most then the odd light shower at times for inland areas for the rest of the day. Mostly cloudy with southwesterly winds tending northeast in the afternoon.
Highs: 10-13

West Coast
Morning mid level cloud breaks away however still expect areas of high cloud, some sun may break through at times. Light easterlies.
Highs: 16-18

Southland & Otago
Any early cloud breaks to mostly sunny weather for Southland and inland Otago, high cloud thickens in the evening. Coastal Otago has a mainly cloudy day. ENE winds develop for most by midday, becoming fresh in the afternoon about coastal Otago.
Highs: 12-13

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz