Residents in Auckland and other North Island regions are enduring more miserable summer weather today, with heavy rain, power cuts, cancelled ferries and warnings that the city’s harbour bridge may be closed due to heavy winds.

Rain, potential thunderstorms and strong winds are playing havoc with the droves of long weekend holidaymakers expected to leave Auckland today for the region’s anniversary holiday.

MetService has placed heavy rain warnings across Northland, Auckland, the Coromandel, parts of the Bay of Plenty and Mt Taranaki, which are due to stretch through most of Friday.

A severe thunderstorm watch is also in place in Northland and Auckland until 7pm tonight.

“Bands of heavy rain and embedded thunderstorms are expected to move across Northland and Auckland today,” MetService said.

Downpours are already drenching the region.

Kaikohe, in the Far North, recorded 32mm in half an hour between 7.30-8am today.

A strong wind warning is also in place for Auckland.

Waka Kotahi NZ said State Highway 25A from Kopu-Hikuai is closed until further notice due to wet conditions, adding a caution to commuters planning a journey to the Coromandel this weekend.

The agency said it will keep a watch on the Auckland Harbour Bridge where motorists can expect to potentially face reduced speeds and lane closures.

The agency said it will close the bridge if winds hit 110km/h.

It also advised morning commuters to be alert to two crashes on Auckland’s motorways that have been cleared now but may still be causing built-up delays.

One crash earlier blocked the right, southbound lane traffic on Auckland’s SH20 Southwestern Motorway after the Hillsborough Rd on-ramp.

“Pass with care and expect some delays until cleared,” Waka Kotahi tweeted.

The other crash had earlier part-blocked the left northbound after the Te Atatu Rd on-ramp, delays are to be expected, it tweeted.

Some ferry services have also been cancelled today, while tens of thousands of Elton John fans will need to get their ponchos and gumboots out for tonight’s and tomorrow’s concerts at Mt Smart Stadium.

Adding to fans’ woes, trains won’t be running and buses to the concert area are expected to be running at capacity.

Elton John is expected to perform in front of a wet crowd in Auckland this evening. Photo / Ben Gibson

Homes in the far east and south of Auckland appear to be suffering power cuts, including in parts of Papakura, Clevedon and towns surrounding the Hunua Ranges, according to electricity provider Vector’s map.

A sweep of homes in the Te Arai area, along the regional border between Auckland and Northland, also experienced power outages earlier on Friday morning but appear to have been reconnected.

An outage at Waiomu, north of Thames, had knocked out power to about 347 homes about 9am today, with supplier PowerCo expecting to restore electricity by 1pm.

The front moved into Northland on Thursday and is now sweeping into Auckland.

It is expected to hang around for the weekend, with the Coromandel’s heavy rain warning lasting into Saturday.

MetService meteorologist Jessie Owen said it is going to be a “very wet start” to Auckland Anniversary weekend and urged motorists to take care.

Miserable summer weather hits Auckland for the anniversary long weekend holiday. Photo / Michael Craig

Motorists battle flash flooding. Photo / Jason Oxenham

“Heavy rain could cause flooding and slips and make travel hazardous so if you’re planning on heading away for the long weekend it’s a good idea to keep up with the forecasts and perhaps consider delaying your travel.”

Aucklanders can subsequently expect heavy rain today, together with gales in exposed places and a chance of thunderstorms as well as with a top of 23C.

MetService said 50-80mm of rain could be expected to fall on Friday.

The temperature will climb to 26C tomorrow, with periods of possibly heavy rain.

Whangārei residents are also being battered by heavy falls with a chance of thunderstorms this morning and are headed for a top of 22C today and 25C tomorrow.

Between 50mm and 70mm could also fall in Northland before 5pm today.

Tauranga and Hamilton will be hit by increasingly heavy rain over today as both cities head to a top of 21C before having possibly heavy falls again on Saturday with a top of 23C.

MetService says 70-100mm of rainfall near the Coromandel Coast, with more falling in the mountains.

In the Bay of Plenty west of Whakatāne, MetService expects between 130 and 180mm to fall, while Mt Taranaki on the west of the North Island will have falls up to 230mm.

Heavy rain watches are also in place for the Wairarapa, Tongariro National Park and Bay of Plenty from Whakatāne, east towards Gisborne.

In Wellington, residents can expect rain developing in the late afternoon and a top of 23C before a cloudy Saturday with a high of 18C.

In the South Island, Christchurch can expect a fine morning and a scorching top of 30C before showers and possibly heavy rain arrives in the evening.

Residents can then expect a major change in temperature as Saturday’s high drops to 20C.

It is part of a cold front that will sweep up the east of the South Island on Friday and Saturday.

Commuters brace themselves against inclement rain and wind. Photo / Michael Craig

Wet weather walkers in Cornwall Park. Photo Michael / Craig

Meanwhile, back in Auckland, Waka Kotahi urged motorists to drive to the conditions.

“Look out for the electronic message boards which will indicate lane closures and reduced speeds, or full bridge closure, and stay within their lane while travelling across the bridge,” the warning said.

“Drivers of high-sided vehicles and motorcyclists are advised to avoid the Auckland Harbour Bridge and use the Western Ring Route on State Highways 16 and 18. Waka Kotahi is working closely with MetService to monitor wind speeds with maintenance crews out on the network ready to react and close lanes on the bridge if wind gusts exceed threshold levels.

“The safety of road users is our top priority and we won’t hesitate to reduce speeds, close lanes or close the bridge if necessary.”

The high winds could also cause delays or cancellations to public transport.

Holidaymakers heading to the storm-ravaged Coromandel Peninsula may want to rethink their plans, with a warning from MetService to expect heavy rainfall for 24 hours from 10am on Friday.

This could cause streams and rivers to rise rapidly, leading to surface flooding and slips making driving conditions hazardous.