Heavy rain is set to drench parts of the South Island this weekend, with forecasters warning of the possibility of flooding and slips.
From midday on Saturday, heavy rain warnings will kick in for parts of Westland, Otago and Fiordland, forecaster MetService said.
MetService's severe weather outlook showed a high confidence of heavy rain in Westland south of Otira on Sunday morning. There was also moderate confidence of heavy rain in Buller and parts of Canterbury.
The extreme weather could bring chaos to those areas, with the possibility of streams rising rapidly.
"Lots of rain is forecast in a short period of time for the lower and western parts of the South Island," NIWA said, noting between 100 and 200mm of rain was forecast in some areas from late Saturday until early Sunday.
"This will result in a rapid increase in river flows as well as the risk of flooding and slips."
MetService said strong winds could also rip through the Canterbury High Country from Saturday afternoon.
"For those planning end-of-year functions and local Christmas parades, the initial part of the weekend offers the most favourable conditions before the front makes its presence felt later on Saturday," MetService meteorologist Mmathapelo Makgabutlane explained.
"This weather system is poised to deliver a substantial amount of rain."
Most of the North Island, meanwhile, could expect isolated showers on Saturday and scattered rain on Sunday.
