Fog shrouded parts of the upper North Island and the lower South Island, causing delayed flights and murky conditions on the roads this week.

The chance of fog remains high from the Waikato to Wairarapa, warns the MetService.

It'd be a wise move for travellers to check the condition of roads with NZTA or the status of flights with airports before heading out today, says the weather organisation.

Places in eastern and central New Zealand will see some sun on Friday, but northeasterlies bring cloud and showers to the north and to the Bay of Plenty.

Meanwhile, a southerly front brings rain to Fiordland and the West Coast.

On Saturday, these features dominate their respective islands; the front sweeps up the South Island while northeasterlies spread the rain further into the North Island, with some possible heavy falls in the Bay of Plenty.

Sunday rounds off the last weekend of autumn with an improving trend, although a southerly could prolong the rain on the east coast of the North Island.

'After last weekend's snow, this is classic autumn changeability,” says meteorologist Tom Adams.

'Temperatures will be mild, but it'll be a cloudy weekend with multiple weather features keeping everyone on their toes. This brings additional uncertainty to the weather models, so if you're planning anything outdoors it will pay to keep an eye on the forecast.”