Frosts and fog could linger around many areas in the South Island but once those burn off, the south can expect a fine day.
The North Island has much warmer temperatures - good news for this afternoon's sold-out match between the Blues and the Hurricanes at Auckland's Eden Park.
Current forecasts are for a few showers to clear the city early this morning, with cloud increasing during the day and northeasterly winds. A temperature of around 15C is expected for the 3.35pm kick-off.
Northland, Coromandel, Gisborne and Hawke's Bay can expect morning showers before fine spells in the afternoon.
The day will be mainly fine from Waikato through to Wellington, with some light rain possible around Taranaki from this evening.
Looking ahead, the current high will move east and offshore later today, with a milder subtropical northerly flow developing, forecaster Weatherwatch says.
By Monday night and into Tuesday, the milder winds will mean warmer-than-average overnight lows - meaning temperatures in parts of the South Island will move from several degrees below normal to several degrees warmer than normal within 48 hours.