Heavy rain and strong wind warnings and watches are in place for a number of locations across the motu on Friday.
National Institute of Water and Atmospheric Research (NIWA) meteorologist Chris Brandolino earlier told RNZ the country was in for a weather "rollercoaster" before temperatures rose into the 30s again next week.
Weather would be unsettled on Friday night and into Saturday, with a day or two of "unusually cool, brisk temperatures for this time of year", he said.
MetService orange heavy rain warnings are in place for the ranges of Buller and the ranges of Westland and Grey districts.
Buller's warning was in place from 9am until 7pm on Friday while Westland and Grey districts warnings was in place from 4am until 4pm.
Up to 90 millimetres of rain could be expected with possible thunderstorms.
As of 5.30am, Fire and Emergency New Zealand said it had not yet received any weather-related callouts on the South Island's West Coast.
Orange strong wind warnings were in place for Wellington and Wairarapa, including Tararua District, from 1pm until 9pm and Marlborough Sounds from 12pm until 7pm.
MetService said the strong wind gusts, of up to 120 kilometres per hour, could damage trees, powerlines and unsecured structures.
"Driving may be hazardous, especially for high-sided vehicles and motorcycles."
A heavy rain watch was in place for Tasman, west of Tākaka, including Nelson lakes National Park from 10am until 7pm.
Canterbury headwaters, north of the Rakaia River, was also under a watch from 6am until 6pm.
MetService said a period of heavy rain and possible thunderstorms could be expected and all locations could approach warning criteria.
Meanwhile, a strong wind watch was in place for Tasman, west of Nelson, from 10am until 6pm, and Marlborough from 11am until 6pm.
But Brandolino said warm air was coming from Australia next week, which would set the country up for potentially high temperatures.
Monday, Tuesday, Wednesday and Thursday would see the eastern North Island and eastern South Island as the places to be with temperatures "well into the 30s" for several days.
"More heat is coming next week, for sure."