A west to soutwesterly airflow lies over New Zealand today, a strong cold southwest change pushes into the lower South Island this afternoon reaching the lower North Island overnight.

Northland, Auckland, Waikato & Bay Of Plenty
Cloudy areas and the odd shower. Long dry spells with some sun possible in the afternoon / evening for Waikato and Bay Of Plenty. Showers and breezy WSW winds pick up in intensity later in the evening or overnight for all. Winds becoming strong about western coastlines overnight.
Highs: 16-19

Western North Island (including Central North Island)
Morning showers then a few afternoon sunny spells break through, later in the evening or overnight rain moves. Breezy westerlies change gusty southwest overnight.
Highs: 13-15

Eastern North Island
Sunny spells, chance of an isolated morning shower about Wairarapa through to Hawkes Bay then clearing, mostly sunny otherwise with easing west to southwesterly winds. Overnight strong southwesterlies move into Wairarapa bringing showers.
Highs: 17-19

Wellington
Sunny spells, overnight rain as gusty northwesterly winds change southerly.
High: 15

Marlborough & Nelson
Mostly sunny, evening showers move into Nelson then pushing into Marlborough overnight. West to northwesterly winds change southwest overnight, gusty about Marlborough.
Highs: 16-19

Canterbury
Mostly sunny, during the evening gusty southwest winds push northwards through Canterbury bringing showers with heavy falls and a risk of hail.
Highs: 14-16

West Coast
A fairly cloudy day. Morning showers about North Westland ease, fourth south heavy rain moves into Fiordland by midday then spreads northwards in the afternoon. Rain eases overnight. Westerlies change fresh southwest in the evening.
Highs: 10-13

Southland & Otago
High cloud with some sun, may be a morning shower (more so for Southland). Heavy showers with a risk of hail develops in the afternoon as southwesterlies freshen, showers ease at night. Snow lowers to 400m in the evening.
Highs: 9-13

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz