Coromandel and western Bay of Plenty residents are being told to avoid unnecessary travel with the peninsula set to be battered by heavy rain and gale-force winds from Wednesday night.
The Thames-Coromandel District Council warns "significant" rain is expected and people need to prepare for flooding, slips, power outages, and road closures.
Council Civil Defence controller Garry Towler said in a statement residents should tie down or secure outdoor furniture.
"Clear your drains and gutters, check that the street drains by your property are clear and check your neighbours," he said.
Motorists are also being warned to "expect the unexpected" and drive to the conditions.
"Avoid unnecessary travel and take care," said NZ Transport Agency Waikato system manager Cara Lauder.
Forecasts suggest periods of heavy rain and isolated thunderstorms between midnight and 3pm on Thursday. Lauder said in a statement that ground conditions in the Coromandel were still saturated due to rain over Queen's Birthday weekend.
MetService has issued a heavy rain warning for the Coromandel, with up to 150mm of rain expected to accumulate.
"Heavy rain may cause streams and rivers to rise rapidly and there is a chance we may need to close some roads," Lauder said.
"Drive to the conditions and watch out for surface flooding, slips, and fallen trees, or branches."
In a statement on Wednesday, WeatherWatch analyst Aaron Wilkinson said most of the North Island will receive rain or showers on Thursday.
Stormy conditions might also hit Northland on Thursday afternoon and parts of north Auckland.
Heavy rain watches have been issued for the north and east of Northland and Auckland north of Orewa, while strong winds watches are in place for Auckland and the Coromandel Peninsula.
