"It's the old switcheroo."
Halfway through the week we can expect to see a classic spring front pushing into the country. On Tuesday evening and Wednesday morning we should get a northwesterly burst of rain with potential of a thunderstorm. The wind will then change to a southwesterly.
"That is classic spring and that's arriving next week.
"It's not perfect for the holidays but it's not that bad. We're New Zealanders we can cope with this."
Duncan warns that some areas in the North Island may get localised flooding as a result of the Australian weather.
"It's not a region, it'll be a valley or a road in a region ... We'll get localised flooding on the west coast of the North Island, anywhere from Kapiti Coast to Northland."
Auckland will get milder weather than centres like Wanganui and the Wairarapa this weekend with more fine spells. But it will get windier as the week progresses with showers on Thursday and Friday.
"Auckland is not looking too dramatic this weekend. It'll be cloudy with the odd shower, rain in the morning and isolated heavy falls on Sunday."
The worst place to be this week is the west coast of the South Island and Taranaki as they are about to get hit hard by wind and rain, Duncan said.
"Taranaki is not one of the better places. It's had beautiful weather this week but this coming week it'll be windy, showery and unsettled for Taranaki in particular."
"The further north you go, the warmer and drier it'll be. Which is good news for Gisborne, East Cape, Bay of Plenty and Coromandel who have had a gutsful of rain."
But it won't all be wet, Duncan explains. There will be plenty of dry spells with areas on the east coast catching lots of sunshine.
Duncan said the best place in the country will be Otago as it's far away from the rough weather.
The Bay of Plenty should have a lovely Sunday morning after a rough week of rain and Waikato and the Coromandel will see some pleasant dry spells. The Bay of Islands will also get some good weather, missing the stormy front and getting nice blue skies throughout the week.
Wellington will get some warm northwesterlies turning into gales and a short burst of cold later in the week.
Queenstown will have an unsettled weather week with strong winds set to rip through the town.
Nelson is set to get some cloud and wet weather but will still hold on to a good amount of sunshine.
Duncan predicts this month could be warmer than average which "ties into the theme of 2016".
"September and October are always crazy chaotic weather months that are all over the place."
