Insurers are warning it will be years before all claims are settled for flood damaged homes, cars and contents in Auckland.

The Insurance Council says so far 15,000 claims have been lodged.

Its consumer affairs manager Sarah Knox says the recent flooding is unprecedented and processing insurance claims will take years.

Knox says for a standard flood, it would take a year to process most claims.

Meanwhile, another part of Auckland is likely to be hit by heavy rain - with fresh watches issued.

MetService says a heavy rain watch is in force for the Hunua Ranges and Coromandel Peninsula for 18 hours from midday today.

It says although total rainfall of between 30 to 50 millimetres would not normally spark a watch to be issued, it may cause problems for the region because of the recent heavy rain.

The Bay of Plenty, west of Kawerau, including the Rotorua Lakes District and Tauranga City, is also under a heavy rain watch for 24 hours from 8am this morning.

And a thunderstorm watch is in place for much of the North Island this morning.

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