At the moment there just seems to be some disagreement between the models in regard to where this other low up north will bear down onto.. will probably just slide SE of here. Long, heavy persistant falls on the way for NE Fiordland/SW Westland.
Then soon some heavy rain or showers on the way for Eastern South Island/Wellington regions as the new ridge sets itself in and depression heads away.
Becoming very cold the next few days over SE Australia... Thickness should lower to 5400 (GFS) over Invercargill by Tuesday.. though personally i'd like to see the ECMWF scenario become fruition.. which could see freezing levels over Southland drop to 700m.
Looking further ahead.. may see rainy easterlies again for the NI.

Any thoughts?
edit, adjustments to title