New Zealand experiences hottest June on record despite polar blast
For once the Guardian’s headline is accurate – more so than the NZ media (with the exception of the NZ Herald) which thinks this is too sensitive and would rather have people complaining about “cold weather”
Average temperatures for the month were 2C higher than normal, with 24 separate locations hitting their own records
New Zealand has experienced its hottest June since records began more than 110 years ago, according to official climate data.
Despite a polar blast that swept up the country last week, figures from the National Institute of Water and Atmospheric Research’s (NIWA) show the average temperature for June was 2C warmer than usual, with twenty-four locations around the country hitting their own record highs.
That makes this June New Zealand’s warmest since NIWA’s seven station temperature series began in 1909.
The warmth was widespread, with every long-term monitoring station observing either above or well-above average mean temperatures. It was particularly warm in Motueka, near the top of the South Island, where the mean temperature of 10.8C was 3.2C higher than the town’s 1981-2010 average.
Of the six main centres, Auckland was the warmest and sunniest, Tauranga was the wettest, Christchurch was the coldest and driest, and Dunedin was the least sunny.
The highest temperature recorded was in Hastings, in the Hawke’s Bay, and Leigh, north of Auckland, both reaching 22C on different days of the month.
The 2C average increase is “a massive shift” relative to normal, climate scientist Gregor Macara said, adding that the previous June record was an average 1.64C higher than usual.
NIWA puts the increase in temperatures down to above-normal sea level air pressure to the east of the country, and climate change.
“North-easterlies are dragging air masses from the sub-tropics, so they are relatively warm. The fact we were having more north-easterlies than normal delivered warmer air over the country than we would typically see in June.”
Sea surface temperatures were also warmer than normal and could be a contributing factor.
“Because we are an island nation, our climate is characterised as maritime, which means it is influenced by the sea. The warmer-than-normal sea surfaces helped to sustain the warmer-than-normal air temperatures,” Macara said.
Underpinning all of this was climate change, he said.
In the past 100 years, New Zealand’s temperature has increased by 1C, which is contributing to the overall warmer temperatures, Macara said.
If warmer winter months persist in the years to come, that could spell trouble for the country’s ski-fields and agricultural sector.
“It will pose increasing challenges on the ski-industry because it will be more marginal to operate earlier in the season with the lack of snowfall, or with temperatures that are too warm to enable artificial snow to be made.”
Earlier in June, two of the country’s most popular skiing destinations – Queenstown’s Coronet Peak and Wanaka’s Cardrona Alpine Ski Resort – had to delay their openings due to the warm weather and lack of snowfall.
Agricultural industries that rely on frosts would also suffer, he said, but added the warmer weather could provide opportunities for re-orienting the sector towards crops that do well in warmer climates.
NIWA forecasters predict a continuation of warm weather throughout the remaining winter months.
New Zealand’s warmest June on record
| Temperature | It was New Zealand’s warmest June on record, with the nationwide average temperature 2.0°C above average. This is just the 13th occasion since 1909 that a month achieved an anomaly of >1.9˚C relative to the 1981-2010 average. Temperatures were above average (0.51-1.20°C above average) or well above average (>1.20°C above average) throughout the country. Twenty-four locations observed their warmest June on record. |
| Rainfall | Rainfall was above normal (120-149% of normal) or well above normal (>149% of normal) for eastern parts of Northland, inland Bay of Plenty, eastern Waikato, Wairarapa, northern Canterbury, southeastern Otago and western Southland. Rainfall was below normal (50-79% of normal) or well below normal (<50% of normal) for parts of Central Otago, South and Mid Canterbury, Nelson, Tasman, inland Whanganui, Gisborne and eastern Bay of Plenty. |
| Soil Moisture | At the end of the month, soil moisture levels were lower than normal for inland parts of Otago. Soil moisture levels were higher than normal for eastern parts of Canterbury and Marlborough. Near normal soil moisture levels were typical for the remainder of the country. |
Overview
June 2021 mean sea level air pressure was above normal to the east of Aotearoa New Zealand. This was associated with more northeasterly air flows than usual over the country. The prevalence of these air flows, occasional low pressure systems that transported warm, humid air down from the sub-tropics, and ongoing background warming from climate change meant it was a very warm start to winter throughout the country. Temperatures were above average (0.51-1.20°C above average) or well above average (>1.20°C above average) throughout New Zealand. Overall, the nationwide average temperature in June 2021 was 10.6°C. This was 2.0°C above the 1981-2010 June average, making it New Zealand’s warmest June since NIWA’s seven station temperature series began in 1909.
There were considerable spatial differences in monthly rainfall totals observed over the country in June. In the North Island, rainfall was above normal (120-149% of normal) or well above normal (>149% of normal) for eastern parts of Northland, inland Bay of Plenty, eastern Waikato, and the Wairarapa. In contrast, rainfall was below normal (50-79% of normal) or well below normal (<50% of normal) for parts of inland Whanganui, Gisborne and eastern Bay of Plenty. For the South Island, rainfall was above normal or well above normal for northern Canterbury, southeastern Otago and western Southland. Rainfall was below normal or well below normal for parts of Central Otago, South and Mid Canterbury, Nelson, and Tasman. Rainfall was typically near normal (80-119% of normal) for remaining areas of New Zealand. By the end of June, soils were drier than normal for inland parts of Otago, and wetter than normal for eastern parts of Canterbury and Marlborough. Soil moisture levels were typically near normal for remaining parts of the country.
Further Highlights:
- The highest temperature was 22.0°C, observed at Hastings on 26 June, and Leigh on 19 June.
- The lowest temperature was -7.4°C, observed at Middlemarch on 19 June.
- The highest 1-day rainfall was 162 mm, recorded at Arthurs Pass on 25 June.
- The highest wind gust was 191 km/h, observed at Cape Turnagain on 28 June.
- Of the six main centres in June 2021, Auckland was the warmest and sunniest, Tauranga was the wettest, Christchurch was the coldest and driest, and Dunedin was the least sunny.
- Of the available, regularly reporting sunshine observation sites, the sunniest four locations in 2021 so far are Taranaki (1331 hours), Bay of Plenty (1299 hours), Marlborough (1291 hours) and Hawke’s Bay (1277 hours).
