‘Exceptional’ July dumps rain at record levels
It’s been the rainiest July in 30 years for New Zealand’s six main centres combined, with 1316mm in the gauges so far.
Two cities have also recorded their wettest July since records began more than 150 years ago.
‘‘It’s been quite exceptional this July,’’ said NIWA meteorologist Tristan Meyers.
‘‘We’ve seen a regime change since the beginning of winter.’’
Meyers said Christchurch in particular had been getting a soaking, with 266mm ‘‘and counting’’ of rain this month. He said it was the wettest month on record for the Garden City, and that their records began in 1864 – 158 years ago.
Meyers said he wouldn’t be surprised if this July became the wettest month nationwide, though he was cautious making that claim before the month’s end.
MetService data revealed both Christchurch (267.8mm of rain) and Dunedin (140.2mm) had recorded their wettest months on record since
1943 and 1962 respectively.
Auckland Airport recorded its secondwettest July since 1962 with 250.6mm, while Hamilton Airport (211mm) and Tauranga Airport (266.1mm) both saw their fifth-wettest Julys.
Wellington Airport was just shy of its fifthwettest July, with 181.1mm.
MetService meteorologist Lewis Ferris said the six locations totalled around 1316mm. ‘‘This will of course change before the month’s end’’.
‘‘The sum of these six stations this month is the largest July total in the last 30 years,’’ he said, ‘‘beating out 2008 which had 1118.8mm.
‘‘It has also overtaken the 1302mm recorded in May 2005 and become the month with the largest total for those six stations.’’
Ferris did caution, however, that some years have missing monthly data, ‘‘so it is possible there was one that could have come in higher’’. Areas outside the six main centres haven’t been missing out on rain either, he said, though for some it’s been a dryer than average July.
‘‘While the six main centres represent a large portion of the population and even more areas have seen above twice their average July rainfall there are places that have recorded less than normal’ rainfall,’’ he said.
‘‘Parts of Gisborne, Hawke’s Bay, Whanganui and Fiordland are below average at this point of the month.’’
Meyers said the reason for the abundance of rain this month was largely down to the La Niñ a weather pattern, more northerly wind, warmer than average temperatures and ‘‘constant’’ feeds of moisture from the sub-tropics.
‘‘It’s been quite exceptional this July. We’ve seen a regime change since the beginning of winter.’’ NIWA meteorologist Tristan Meyers