Clean ups are underway as the West Coast recovers from a deluge of rain.

Franz Josef experienced its wettest 24 hours in more than four decades - prompting a state of an emergency for southern Westland.

State Highway 6 from Fox Glacier to Haast has been damaged by slips and flooding - it's closed until at least Monday.

Westland mayor Helen Lash says the road is currently not passable.

"The road has slumped, it's got cracks in it - and we're not prepared to take any risk with putting anybody on that part of the road."

LISTEN ABOVE

• Scorcher! Areas to hit 30C for the first time in 21 months