New Zealand endured its wettest and fourth warmest July ever: NIWA
Wellington: Aotearoa New Zealand has just endured its wettest and fourth warmest July ever, NIWA says.
In its monthly summary, the National Institute of Water and Atmospheric Research (NIWA) said from 11-31 July, five separate weather events delivered enough rain to cause flooding around the motu.
The culmination of these frequent rain events led to 20 centres experiencing their wettest July on record and near-record wet months for a further 25 locations.
The vast majority of the country had well above normal rainfall with Wellington and Dunedin experiencing their wettest July on record while Auckland and Hamilton saw their second and third wettest respectively.
The exceptions were coastal parts of Gisborne, Hawke’s Bay and northern Wairarapa, which experienced below normal rainfall.
In Christchurch, it was the wettest month (of any month) on record. The 310mm of rain recorded there was the first time that more than 300mm of rain fell in one month since records began in 1863. It represented about half of the rain the city typically received over the course of a year.
Frequent wet weather meant that it was also a cloudy month and this was reflected in warmer than usual overnight temperatures with both the North and South Islands experiencing record or near-record high mean minimum (overnight) temperatures.
Overall, it was New Zealand’s fourth-warmest July on record, with the nationwide average temperature (9.9degC) 1.3degC above average, NIWA said.
NIWA said the wet, warm weather was the result of an overall air pressure pattern that saw higher than usual pressures to the northeast and southwest of the country and was associated with more northerly quarter air flows.