The "beaten up old windbag" of ex-Cyclone June is sitting just north of Auckland, preparing to bring rain and strong winds to the city, the MetService says.
A few small thunderstorms have been recorded in areas such as Whangarei and Warkworth as the bad weather bears down on Auckland.
"That little cluster of persistent rain will just drift across Auckland over the next several hours, and with a clockwise flow of wind around the low," said MetService forecaster Dan Corbett, about 11.40am today.
He said a "boomerang shape" band of rain which came in on northeast winds yesterday was currently sitting over the central part of the country from Taranaki to Wellington and down to Marlborough.
When that eases away later today it will be replaced by strong southwesterly winds, which Mr Corbett described as "the sting in the tail".
"That's going to wrap in behind that low as it comes across Auckland through the rest of the afternoon," Mr Corbett said.
Strong winds are expected later today, with some "already picking up and strengthening" in the Far North.
"Cape Reinga for instance has already seen wind gusts of up to 100km/h," Mr Corbett said.
"Those stronger west, southwest winds are funnelling their way down Northland as the low tracks across.
"There could be potential wind gusts maybe as high as 100km/h - 120km/h to western parts of Northland, across some exposed parts of the harbours of Auckland throughout the afternoon, and then further east to Coromandel."
A severe wind warning is in place for Northland, Auckland, the Coromandel Peninsula and the western Bay of Plenty areas.
The band of rain sitting across the lower North Island is expected to drift away this evening, with wind and rain easing off by tomorrow.
"So there still is some wind, some rain to come in places but by tonight we are sort of beating the back of this thing out the barn door and closing it quickly, and it improves for tomorrow," Mr Corbett said.
"Tomorrow's more of a westerly wind day with some showers, but sunshine returns to quite a few places."
Earlier WeatherWatch analyst Peter Duncan said widespread damage was not expected because the storm system was significantly weaker than Cyclone Wilma which hit the upper North Island the same time three years ago - causing millions of dollars worth of damage.
While some debris had been blown onto Northland roads early this morning, there have been no reports of serious damage so far.
Motorists are advised to take care when driving.
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