Erratic West Coast weather patterns raise questions about how region will cope with climate change

After a month's worth of rain came down in less than 48 hours in Greymouth, there are fears the West Coast will see more dramatic weather events due to climate change.

Its geography close to the Southern Alps and the Tasman Sea make the area especially vulnerable.

"There's only 70 odd miles between the Tasman and the top of the mountain range, the water comes down very fast so the events come and go fairly quickly," Greymouth Mayor Tony Kokshoorn told 1 NEWS.

The Ministry of Environment predicts rainfall on the West Coast could increase by up to 29 per cent by 2090 meaning we're likely to see extreme weather like yesterday more often and the risk of flooding could escalate.

This latest downpour hasn't been all bad news though according to Mr Kokshoorn.

"The farmers were screaming for rain then we declare a drought and the next morning down it comes.

"That 150 millimetres certainly cleared up any doubts about the drought continuing," he said.

What is continuing for the region is the threat of more severe weather events to come.