Rain clouds are lining up to smash the West Coast, with MetService warning over half-a-metre of rain is expected to fall over the next few days.
"An extended period of moist northwesterlies, with a number of embedded fronts, is forecast to affect the South Island bringing periods of heavy rain to the West Coast and the Southern Alps," the weather forecaster says.
"The heaviest rain is expected in Fiordland and Westland from Harihari southwards and the headwaters of Otago Lakes and Rivers."
Peak intensities of 15 to 25mm per hour are predicted to fall during Monday and Tuesday, with thunderstorms possible.
Heavy rain warnings have been put in place in place for Fiordland, the Southern Lakes and Westland south of Harihari.
"Please note that this is a significant rain event and that rainfall accumulations are likely to exceed 500mm in some places over a four- or five-day period," MetService warns.
"Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous."
Newshub.
