New Zealand is preparing for a sharp transition in its weather patterns as the King’s Birthday weekend approaches. After a month defined by high pressure and exceptionally dry conditions, a significant weather system is set to sweep across the country, marking the start of the meteorological winter on June 1.
MetService meteorologist Ngaire Wotherspoon confirmed that the period of settled weather is coming to an end. “It’s been a very, very dry and settled May, with high pressure dominating the weather situation,” Wotherspoon noted. “We are expecting a couple more days of that before quite a marked change over the weekend.”
A Record-Breaking Dry Spell
The South Island has experienced an extraordinary lack of rainfall, particularly in Christchurch. Christchurch Airport has recorded only 5.4mm of rain for May—roughly 10% of its typical 58.4mm average. With the city’s record for the driest May standing at 11.2mm, set in 2012, it is highly likely that this month will go down as the driest on record for the city. This dryness aligns with earlier forecasts regarding the development of El Niño, a climate cycle that often results in drier conditions for eastern and northern regions of New Zealand.
The Weekend Forecast: Rain and Humidity
The incoming weather system is expected to bring a stark contrast to the recent dry conditions. Orange-level heavy rain warnings have been issued for several regions, including the West Coast and Tasman, with the impacts expected to begin Sunday and persist into next week. The north and west of the South Island, specifically the ranges of Westland, Buller, and the Richmond and Bryant ranges, are expected to bear the brunt of the heavy rainfall.
In the North Island, the effects of the system are likely to intensify further north. According to Wotherspoon, “The further north you get in the North Island, the more rain you’re probably going to be seeing,” with significant rainfall expected from the central plateau, New Plymouth, and Gisborne northward.
Those looking to avoid the most severe conditions may find shelter in Canterbury and Otago, which are currently positioned to be the least affected areas due to the northerly flow of the weather system.
Looking Ahead: A Humid Winter Start
Beyond the rain, New Zealanders may experience unseasonably warm conditions. The incoming system is expected to push overnight temperatures 4 to 8°C above the typical May average. As the country transitions into winter on June 1, these temperatures could lead to what Wotherspoon described as “some pretty sticky nights ahead.”
If the current trends continue, regions that have missed out on their usual winter rainfall may face ongoing concerns regarding dryness as spring approaches. For now, residents in affected areas are advised to monitor the ongoing heavy rain warnings as the country shifts from a record-dry month into a humid and wet start to the winter season.