(File image) Photo: RNZ / Richard Tindiller
Ferry passengers will face further disruptions on Monday after strong winds and huge swells canned sailings over the weekend.
Two Interislander sailings between Picton and Wellington were cancelled on Sunday, while two further sailings were delayed by hours on Sunday night due to the swells.
One of those was the Kaitaki, which was due to leave Wellington at 8.30pm with more than 800 passengers on board.
In an email sent to passengers just after 10pm, seen by RNZ, Interislander apologised for the inconvenience of the delay.
"We will be commencing loading asap but will not be leaving Wellington until the Master is comfortable to depart due to rougher sea conditions than forecast - this could be at least 4 HRS," the email said.
"If you wish to not travel tonight please advise staff but keep in mind that our ships are fully booked for the next week."
The Kaitaki finally set off about 1am on Monday, according to ship tracking website MarineTraffic.com.
The Kaiarāhi, which had 500 passengers on board, was also delayed for hours before setting off from Picton just before midnight Sunday.
Further disruptions were in store on Monday, with two sailings of the Aratere - at 6.15am from Wellington and 11am from Picton - cancelled.
However, scheduled Kaitaki and Kaiarāhi sailings went ahead.
Interislander's fleet operations manager Taru Sawhney said both sailings managed to depart, but were delayed due to the unseasonably high swells.
Sea conditions in Cook Strait had been quite different to what was forecast yesterday.
This was due to the "funnelling effect" from the winds that happens sometimes with a high pressure system.
A wind swell and a sea swell had combined to produce the high swell conditions on Sunday night.
"They're unseasonal, they're mostly caused by southerly fronts."
The conditions were picked up and monitored from a live feed supplied by the weather authorities.
Once it was decided it would be both comfortable and safe for passengers services had been restarted, Sawhney said.
Passengers due to sail on the Kaiarāhi had been warned of the rough conditions and offered the chance to change to another sailing.
However, they were also told services were full at present due to the amount of disruption caused by the weather over the festive period so replacement services might be hard to find.
"Most of them travelled with us last night."
Passengers were also able to opt to cancel and obtain a refund, Sawhney said.
MetService meteorologist Alwyn Bakker expected rough conditions to continue in Cook Strait on Monday and while they might ease for a while tomorrow the rest of the week could still be challenging.
"So this week, still looking a bit choppy out on the seas."
Meanwhile, Bluebridge had cancelled four sailings on Sunday, and five on Monday, with further cancellations likely.
It said conditions were likely to remain unsettled until Monday evening.
"Customers impacted by these cancellations will be contacted by our team for alternate sailing options."
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