The influence of the La Niña remains with us and has helped us to have a reasonably worry free year in terms of a lack of rain. Just when we think we might be falling a little short, the following month often compensates. July’s rainfall fell within the normal range across the region but some areas got more than ample amounts. The Heretaunga Plains had 140% of average July rainfall and the Ruataniwha Plains 122%.
July’s river flows sat within the normal range, while soil moisture tracked above normal. A good share of our groundwater levels were still normal or above normal for the time of year, though a drier than usual June nudged upwards the number of below normal wells. Weather systems from the north stoked our temperatures, with July being a warmer than usual month and soil temperatures finishing July on about 10°C.
There is still a good chance we’ll see a La Niña this summer and a negative Indian Ocean Dipole event is currently underway. The latter enhances our chances of good spring rainfall. Seasonal weather predictions keep to a familiar story – lower than normal sea level pressures are expected to the northwest of the country and higher to the east, allowing more of those northerly and easterly flows to guide our weather. That means rainfall is expected to be in the normal range and temperatures persisting above average. We’ve had some wet spring seasons in the last few years, which hasn’t saved from punishing summer and autumn droughts. So all eyes will be on whether that “triple-dip” La Niña settles in for the summer.
Percentage of Normal Rainfall
Dr Kathleen Kozyniak
Principal Scientist Air
Hawke’s Bay Regional Council
