Retrospective - December to February Outlook

Neutral conditions (neither El Niño nor La Niña) were (correctly) projected for the summer period. In the New Zealand region, lower than normal pressures were expected southeast of the Chatham Islands, with enhanced south-westerly winds over New Zealand. Whilst observed pressures were lower than usual southeast of the Chatham Islands, and more southwesterly winds than usual were experienced over the country, the stand-out feature of summer was the unusual prevalence of anticyclones (highs) over both the Tasman Sea and also well to the east of the North Island.

Predicted rainfall: rainfall is likely to be near normal or below normal in the north and east of the North Island, and near normal elsewhere.

Outcome: Summer rainfall was below normal north of Taupo and across the eastern North Island. Near normal rainfall was observed along a narrow coastal strip from Wanganui to Wellington, as well as across most of central Otago, Southland, Fiordland, Buller, Nelson, Marlborough and North Canterbury. It was drier than forecast for much of the Manawatu-Wanganui region, as well as south Canterbury, coastal Otago, and Westland (with below normal summer rainfall generally recorded). In contrast, it was wetter than projected for alpine areas around Mt. Cook and Stewart Island.

Predicted air temperature: Summer temperatures are likely to be near average or below average in western areas of both Islands, as well as the east of the South Island, and near average elsewhere.

Outcome: It was typically warmer than forecast. Near average summer temperatures were generally observed along the western coastline of both Islands, whilst near average to above average summer temperatures were recorded elsewhere.