MetService says there could be a threat to life from what it is calling an "impactful" event.

Up to 320mm of rain could fall in Northland in 48 hours from 4pm this afternoon, MetService is warning.

A number of other watches and warnings are in place across the country in what MetService is calling an “impactful” weather event.

MetService meteorologist John Law said the heaviest rainfall was expected from Northland to Bay of Plenty and its intensity and duration would bring “threat to life from dangerous river conditions, significant flooding, and slips”.