We’ve had contrary weather of late. March was very dry, April very wet, May was very dry and now June was wet. The first month of winter brought ample rain, 123% of the month’s average. Northern areas especially received a large share, while the Heretaunga Plains was the one area that fell short of average June rainfall. It could potentially end July having had three consecutive months of below normal rainfall.
The month’s rain helped river flows reach near normal June levels, similarly groundwater levels. Soil moisture levels across the region tracked near or above median levels for the time of year. Air temperatures in June were impressive, with daytime temperatures 1.5 °C warmer than average and overnight temperatures a mighty 2°C warmer.
El Niño conditions have established and a very strong event seems likely. Some of the past very strong events, such as the 1982-1983 and 1997-1998 events, didn’t turn out well for the region. They brought significant droughts. El Niño events can play out quite differently so it’s not guaranteed that extremely dry conditions will eventuate on this occasion but it’s wise to be prepared in case. One countering feature is that sea temperatures have been relatively warm around the country. The region’s dry spells are more associated with colder seas.
The predicted pressure pattern for the next three months suggests a westerly flow will dominate. It’s to be expected in El Niño conditions. The pattern has higher than normal pressure west and north of New Zealand and below normal to the south and northeast. Rainfall forecasts suggest we could be short of rain over the period, while temperatures remain near or above average. On the bright side, the region’s water resources are in a pretty good state, for now at least, as we face the possibility of drier weather.
