Because New Zealand is quite long (870 miles/1400 km from Cape Reinga to Bluff), surrounded by ocean, and dotted with mountains, there's a lot of climatic variation. Most cities are on the coast, which tends to be milder than inland and mountainous places. The north of the North Island is subtropical, whereas the south of the South Island is temperate, with alpine and other sub-climates in between.
May is the last month of autumn in New Zealand. In general, you can expect moderate daytime temperatures (a mid-weight jacket for daytime wear would be adequate in most places), though nights are cooler, and rainfall is higher than in the summer.
In the northern North Island (Northland, Auckland, the Coromandel Peninsula), May high temperatures can still reach 65° F (18° C). You're unlikely to want to go swimming in the sea in May, although beach walks can still be very enjoyable. Further south, cities like Wellington and Christchurch can be quite cool in May, with average highs around 57° F (14° C), and colder nights. Mountainous areas on both islands, but especially the south, may get snow in May, although ski season doesn't start till June.
New Zealand is quite a wet country and rain should be expected at any time of year. In general, the further north you go, the higher the chance of rain. For instance, Auckland receives almost double the amount of rain as Christchurch in May. So, May can be quite wet, but less so than the winter. Pack a raincoat and an umbrella, because you'll almost definitely need them.
Crowds and Costs
May is not a busy time for tourism in New Zealand. May is not especially warm, so travelers seeking sun and beaches are out of luck, but neither has the ski season started yet. The attractive autumn colors, particularly in the south, have usually made an exit by May. But, travelers who do come will find lower accommodation prices, cheaper car rentals, and plenty of sightseeing opportunities that don't require long days outside.
Where to Go
As a rule, the north of New Zealand is cool and wet in May, and the south is cold but without significant snowfall. There are no bad places to go in May, but where you go should depend on the kinds of experiences you want to have.
Rotorua and Taupo, in the central North Island, are popular throughout the year because of their natural beauty and strong Maori culture. They're also full of natural hot springs, from fancy spa resorts to natural pools out in nature. May is a great time to enjoy these, because a hot spring bath is much more appealing when the weather is cold, which is can be in the central North Island in May.
If you're seeking beautiful mountain vistas but aren't into skiing, May is actually a good time to hit the mountains of the South Island. In winter, snow can block some roads and ice can making driving challenging, but this is less of a problem in May (although always check local conditions, because mountain weather is notoriously changeable). Places like Queenstown, Wanaka, Arrowtown, Lake Tekapo, and Aoraki Mount Cook are beautiful at this time of year.
Northland is known as the Winterless North, and while May isn't quite winter yet, it's true that Northland doesn't get as cold as other places further south. If you're seeking sun, there's a strong chance you'll get this in Northland in May (although it gets a lot of rain, too!) Nelson, at the top of the South Island, often holds the official title of sunniest city in the country, and nearby Golden Bay, Abel Tasman National Park, and the Marlborough Sounds are good places to enjoy outdoor sightseeing when the sun is shining. There's a higher-than-average chance that it will be shining in Nelson in May.
What to Do
Factor some indoor sightseeing into your itinerary if traveling in May, as you may need to retreat inside to get out of the weather. The big cities—Auckland, Wellington, Christchurch, Dunedin—have plenty of great art galleries, museums, restaurants, and other indoor tourist attractions. Other smaller places have a good share too, like the unmissable Treaty House in Waitangi, and Hobbiton in Matamata.
When the weather's good, you can also enjoy outdoor sightseeing activities, like cruises on Milford Sound or Doubtful Sound in Fiordland, dolphin, and whale watching in the Bay of Islands and Kaikoura, and wildlife spotting on the Otago Peninsula. In fact, you don't even need perfect weather to enjoy these activities, and a bit of rain adds to the atmosphere.
Hiking and long-distance trekking can also be enjoyed in May, but sticking to lower-altitude trails would be better. Conditions in the Abel Tasman National Park or the Egmont National Park can be good in May, and booking accommodation in Department of Conservation (DOC) huts on multi-day treks will prevent the need for camping.
Auckland Comedy Festival. Local and international acts perform throughout Auckland, from tiny basements to large theaters.
Auckland Writers Festival. Avid readers won't want to miss this literary event, which brings together writers, thinkers, and readers from around New Zealand, and the world. It doesn't just feature 'traditional' writers, and you can expect talks from other public figures like politicians or musicians.
Traveling to New Zealand in May? Check out these great itineraries
New Zealand's Ultimate Tour - 13 Days. Perfect for first-timers, this 13-day itinerary covers an epic variety of landscapes and activities that only New Zealand could offer.
New Zealand's North Island - 7 Days. Explore the beauty of New Zealand's North Island, from the foodie's haven of Wellington to stunning Tongariro National Park.
New Zealand Cities, Parks, and Mountains - 12 Days. This 12-day tour features a perfect mix of adventure and relaxation. Explore New Zealand's cities, mountain landscapes, native bush, and beaches.