The Christmas weather is unstable – but it's a bit hard to say

A flawless stayThe chances of a long period of fine during the Christmas holidays are not very encouraging, but the absence of a clear meteorological trend el nino calls the caution of the forecasters.

Niwa's principal investigator, Chris Brandolino, said the weather may be uncertain over Christmas week, but the weather may be mild.

Low tropical conditions were emerging in the tropical tropical ocean, but the atmosphere had not followed. This means that the ocean and the atmosphere are not coupled, Niwa said in his seasonal weather forecast from December to February, traditionally the summer months.

El Niño has not been blocked, which means that the weather could be a little more likely to go up and down, with "episodes of stable weather, episodes of unstable weather," said Niwa Ben meteorologist Noll Wednesday. "It's something that could be a theme as we go through the month of December."

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Weather conditions were unstable throughout the country in the early days of December, as two low-pressure systems brought rain, Noll said.

But in the second week of December, the atmospheric pressure was above normal. "So, potentially, a well-established weather period at the time of entering, say the middle of December." But the high pressure system bringing this time might not be lived long.

"As we approach the last stages of the month, some sub-seasonal indications – the indications we are looking at on a weekly time scale – suggest that the situation could become a little more volatile, potentially towards the end of the month."

But similar orientations – in the time scale of three to four weeks – experienced a "difficult time" in November. He "really did not talk about some of those heavy rains," Noll said. The inability of the orientation to grasp the magnitude of the rains later in November was in the minds of forecasters as they were gearing up for December.

The forecast was "a little difficult" because of the lack of a key player in climate change.

If the lack of coupling between the atmosphere and the ocean in a way typically associated with an el nino event persists, each month may have a somewhat different flavor throughout the summer , unlike last summer with its persistent heat.

"We expect increasing variability over the next two weeks in early December, and this trend is expected to continue into the second half of the month," said Noll.

Looking at previous years with similar climatic characteristics to those of this year, "this shows that we could be on a more serene track for January". According to some indications, January could be more stable with below-average rainfall in perhaps large parts of the country, but its confidence in this forecast was "relatively low", "out of 10, maybe it would be five or six".

"There is some uncertainty – again, weak climatic factors that increase uncertainty," he said.

Niwa's outlook shows that the country as a whole has a one in two chance of having average or above average temperatures during the three summer months. A colder than average summer is the least likely result.

It is believed that the upper half of the North Island has roughly the same chances of having precipitation near normal or below normal. The west of the South Island is considered to have about the same chances of normal or above normal rainfall. The rest of the country is most likely to have rainfall around the normal range.