Civil Defence has ordered an evacuation of low-lying parts of Westport, before the already heavy rainfall becomes more intense tonight.
A red weather warning is still in place.
Emergency personnel and an Air Force helicopter are on-hand to help with the evacuations.
Forecasts show the situation could be more severe than last July, when hundreds of homes in Westport were damaged, and some left unliveable.
Māni Dunlop gets the latest from RNZ reporter Samantha Gee who is in Westport.
