Northern and western parts of the South Island are expected to be “pummelled” by heavy rain from Tuesday through to Thursday.
That's the forecast from MetService who've issued severe weather warnings for multiple areas of the south.
"A complex trough of low pressure, preceded by a moist northerly flow, is expected to move onto New Zealand from the Tasman Sea on Tuesday, stay slow-moving on Wednesday, then move eastwards across the South Island during Thursday and Friday," MetService says.
"This weather system is forecast to bring an extended period of northerly rain to northern and western parts of the country, where Heavy Rain Warnings and Watches are in force."
Orange rain warnings have been issued to the Tasman District west of Motueka, the Malborough Sounds, Bryant and Richmond ranges, Buller and the Canterbury lakes, Buller and Westland as well as Mount Taranaki in the North Island.
MetService is expecting 300mm to 500mm of rain in these areas, warning that the heavy rain might cause surface flooding and slips.
Some areas like the Tasman district can expect 700mm to 800mm of rain.
Parts of the Tasman District, including Nelson, as well as the headwaters of the Canterbury lakes and rivers are predicted to be soaked with heavy rain from Tuesday through to Thursday.
The incoming storm is being referred to as an “extended period of significant heavy rain.”
Northland is also expected to be hit with heavy wind and rain with a strong wind warning issued for the area.
The heavy rain watch for Northland starts at 6pm on Wednesday and runs until 9am on Friday. The strong wind watch starts at 8pm on Tuesday and runs until 9am on Friday. MetService are warning severe gale could hit exposed areas.
Motorists in affected areas have been advised to drive with caution as surface flooding and slips could cause accidents.