The ferry crossing between the North Island and South Island occasionally deals with delays or even cancellations due to the weather conditions. Severe weather can happen at any time of the year. Ferry delays or cancellations are out of anyone's control.
Here are our recommendations about how to deal with or plan around ferry delays or cancellations:
When planning your road trip, book your ferry ticket as soon as possible. Either book a (flexible) ticket direct from any of the two ferry companies - Bluebridge and Interislander - or use Spaceships' flexible ferry voucher AND turn that voucher into a booking asap. That way you are covered if all of a sudden there is a run on your desired sailing date due to weather-related disruptions in the days before. And you avoid missing out due to it being peak season.
DON'T MISS OUT, BOOK YOUR FERRY CROSSING EARLY.If your ferry gets cancelled, you'll need to go to the ferry terminal. If you are waiting online, via email or on the phone you will be at the back of the queue.
Contact Spaceships if you need to request an extension of your hire due to ferry delays or cancellations. Please keep in mind that extension requests are subject to availability.
Travel disruptions due to severe weather are also one of the reasons why it is recommended to get travel insurance before you travel to New Zealand.
Info about Cook Strait (the stretch of water between NZ's North Island & South Island)
Wikipedia: "Cook Strait (Māori: Te Moana-o-Raukawa) separates the North and South Islands of New Zealand. The strait connects the Tasman Sea on the northwest with the South Pacific Ocean on the southeast. It is 22 kilometres (14 mi) wide at its narrowest point and is considered one of the most dangerous and unpredictable waters in the world. Regular ferry services run across the strait between Picton in the Marlborough Sounds and Wellington." (source)