UPDATE 3.38pm: A red heavy rain warning has been issued for the Bay of Plenty and Coromandel.

MetService issued the warning at 2.40 pm on January 31 and advised that a further assessment would be made at 9pm.

A red alert means that the forecast for the region is extremely heavy rain.

Read more about the red heavy rain warning here.

Image: MetService.

Earlier 1.55pm: A state of emergency has been declared in Northland as more than 200 millimetres of rain is predicted to fall in some parts of the region.

A statement from the Northland Regional Council said the emergency declaration was requested by Northland Civil Defence Emergency Management (CDEM) Group Controller Graeme MacDonald, and signed by CDEM Group chairperson Kelly Stratford.

"An Emergency Mobile Alert advising of the declaration is being sent to phones in Northland which are capable of receiving the alerts."

The state of emergency is effective as of 1pm Tuesday 31 January for an initial period of seven days.

Earlier 6.32am: Schools are closed and Aucklanders are urged to stay home today as the city braces for another storm that could be more dangerous than Friday's massive flood.

Red heavy rain warnings (the highest-level warnings) are in place for Northland, Auckland north of Orewa and Coromandel Peninsula.

The city north of Orewa is on a red alert for heavy rain from four this afternoon until 7am on Wednesday morning while the rest of the city is under an orange warning.

In the north of the city up to 120mm of rain over 15 hours is expected with up to 80mm everywhere else.

While that's nowhere near the record breaking amounts that pounded the city last week, emergency officials say the ground is so saturated even ordinary rainfall will cause slips and more flooding.

Orange heavy rain warnings are in place for Auckland from Orewa southwards, Great Barrier Island and Bay of Plenty.

As well, gale force easterly winds are expected to bring down a significant number of trees onto roads and power lines.

Officials are urging businesses to stay closed for the day.

Follow latest updates here: