Forecasting the weather can be a tricky business, especially weeks out. But NIWA's Chris Brandolino has taken a punt at predicting what Kiwis can expect over the Christmas period.
On Monday, NIWA released its seasonal climate outlook for summer, forecasting above average temperatures, elevated humidity levels, and other patterns consistent with moderate La Niña conditions.
"Although patterns of higher than normal pressure and drier conditions are expected to start summer, moist, sub-tropical disturbances are expected to reach the country occasionally, particularly the North Island and northern South Island. These systems can cause areas of heavy rainfall and flooding."
Appearing on The AM Show on Tuesday, Brandolino, NIWA's principal scientist, was asked by host Duncan Garner if he could pinpoint what the weather might be on December 25.
"Right now, it is leaning and favouring warm and settled weather for the Christmas period... the day before, two before Christmas, day or so after Christmas, in that Christmas period, it is favouring settled and dry," Brandolino said, before cautioning that that could change.
"Duncan, we are three weeks away, more than that."
While it may be difficult to know what Mother Nature may have in store for us on Christmas day this far out, Brandolino ruled out a white Christmas - unless you're at the beach with the white sand or on top of one of New Zealand's snowy mountains.
Looking past December and at summer overall, Brandolino told The AM Show it can be said with "high confidence" that it will be a warmer than average summer.
"When NIWA gives our climate outlook for a long period, three months, what we are trying to do is define Mother Nature's personality. Weather is her mood. Most times during that period they are going to be aligned, but sometimes they won't be," he said.
"Just because our expectation is for Mother Nature's personality is to be warm or warmer than usual, doesn't mean there won't be a cool day or a cool period."
In regard to rainfall, Brandolino said that last summer, much of the North Island only received about 50 percent of what is typical during the period.
"It would be very unlikely to see the same outcome this summer. In other words, a dry summer for the North Island, pretty darn unlikely. In fact, for much of the North Island full stop, we think that rainfall is likely to be near normal or above normal."
We may also see more flooding events due to La Niña and the "moisture coming from the north and east".
"For the South Island, that is one place which has our attention when it comes to dryness."
Brandolino says if there is going to be below normal rainfall, odds are for that to be in the central and lower South Island.
"More humidity than normal, especially for the North Island. Our seas are running warmer than average for the time of year. We have got to watch the tropical cyclone risk later on during the summer."
