The New Zealand Transport Agency (NZTA) says there is now a surge in traffic around the newly opened IKEA store in Auckland.
It said people going there after work is causing queues on Carbine Road. Traffic is still flowing in Mt Wellington, and on the motorway.
Earlier, the agency said all of IKEA's car parks were full and overflow parks were being used.
For much of the day, the feared traffic jams failed to eventuate.
A predicted IKEA stampede and traffic jams to the Swedish giant's new store at Mt Wellington appeared to have been avoided.
Eager shoppers had gathered outside the Mt Wellington store, with some telling RNZ they arrived as early at 4.45am.
Drivers had been warned to expect long queues on the opening day, with traffic analysts expecting crowds of up to 20,000 a day to visit the store.
In a "worst case" scenario, they predicted a 40-minute crawl on the nearby motorway and another 40 minutes to find a car park.
Auckland Transport real time operation manager Claire Howard told Checkpoint through good communication and public transport use they've avoided that.
"It is not like a concert where we know we are going to get 50 thousand people show up at this particular time so we have to be prepared for a worst case scenario.
"And you know if we weren't implementing those plans that we have got in place today and right now then you would likely be seeing more congestion on the network."
Auckland Transport was predicting more traffic in the area this weekend with a nearby A league match between Auckland FC and the Wellington Phoenix scheduled on Saturday.
The IKEA store opened officially at 11am, while the carpark was opened to shoppers at 8.30am.
An RNZ reporter at the store estimated around 800 were gathered outside before the doors opened, including Bernie, who had driven over two-and-a-half hours from Papamoa, saying he and hsi wife had waited six years for the opening.
"We chose to open at 11am so that we avoid the morning traffic," IKEA's NZ manager Johanna Cederlöf said.
Other shoppers told RNZ traffic had not been as bad as anticipated, and the carpark was not yet full.
Speaking to media following the ribbon cutting, Prime Minister Christopher Luxon welcomed what he said was a "long time coming" and evidence of "really good foreign investment in New Zealand".
"This is great for competition, this is great for consumers across New Zealand and actually, you've seen other retailers welcome the move as well."
Hundreds lined up to enter NZ's first IKEA store. Photo: Marika Khabazi / RNZ
Asked whether welcoming the Swedish retailer with open arms is a slap in the face for local businesses, Luxon said competition will "make them better".
"They should step up and compete, and I know they will.
"There are a lot of retailers that are welcoming the competition. It will make them better and it will actually be a good thing for New Zealanders."
What will the roads be like in the coming days?
NZTA on Thursday also warned of busier roads around Mt Wellington on Saturday.
Auckland Transport Operations Centre (ATOC) Manager Claire Howard said substantial crowds were expected at IKEA for weeks or even months which would have a substantial effect on the transport network across Auckland.
"Surrounding streets in Mt Wellington will also be busy, with forecast delays of up to 40 minutes on Mt Wellington Highway in peak traffic."
ATOC - a joint Auckland Transport and NZTA venture for managing the network in real time - has been working with the retail giant to ensure their traffic management plan minimises the traffic impact as much as possible. It would be actively managing light signals and diverting traffic where possible as congestion levels increase.
Congestion was expected to be at its worst during peak hour during the week and on Saturdays between 1 and 4pm - particularly heading northbound from South Auckland toward Mt Wellington.
Staff would be on the ground at Sylvia Park Train Station to help direct people to the store who were travelling by train.
IKEA's NZ manager Johanna Cederlöf, said for anyone who wasn't in Auckland or who wanted to avoid the opening day crowds, they could shop online from midnight as a way to beat the crowds.
Ulla Bennett drove from the North Shore at 4am to be one of the first in line. Photo: RNZ / Marika Khabazi
Shoppers enter the store. Photo: Marika Khabazi / RNZ
More shoppers enter the store. Photo: Marika Khabazi / RNZ
Prime Minister Christopher Luxon was on hand for the ribbon cutting. Photo: Marika Khabazi / RNZ
Prime Minister Christopher Luxon Photo: Marika Khabazi / RNZ
People queue to enter IKEA on its opening day in Auckland Photo: Marika Khabazi / RNZ
Mel has been waiting here since 4.45am, she says. Photo: RNZ / Finn Blackwell
IKEA's famous meatball Photo: Marika Khabazi / RNZ
Shoppers gathered outside. Photo: Marika Khabazi / RNZ
IKEA is opening at 11am to avoid morning traffic. Photo: Marika Khabazi / RNZ
Traffic analysts are predicting a 40-minute wait to enter the IKEA carpark at peak times Photo: Marika Khabazi / RNZ
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