Concerns over how the already soaked Northland will cope with more localised downpours

Heavy rain watches and warnings cover the region, Auckland and Coromandel - until early Thursday.

Power outages and road closures have hit parts of Northland and Auckland - and more than 200 homes in Mangawhai have no supply because of downed powerlines.

MetService Metereologist Katie Lyons says the persistent rain predicted in coming days is a flooding risk

She says the worst impacts come when persistent rain and localised downpours combine.