Niwa climate scientists are predicting a "warmer than average" autumn for Otago and Southland.
Principal scientist Chris Brandolino said between March 1 and May 31, temperatures in Otago and Southland were "most likely" to be above average, while rainfall totals, soil moisture levels and river flows were likely to be near normal.
The prediction was based on an El Nino climate cycle now occurring in the central Pacific; regional circulation air flows; and continuing warmer-than-average sea surface temperatures in the Tasman Sea.
"For the autumn season (March 1 to May 31), the regional circulation for New Zealand is likely to be influenced by the tropics to the north and the Tasman Sea to the west.
"Furthermore, when the tropics become the dominant driver of weather patterns, easterly quarter winds will become more likely. Otherwise, westerly quarter flow anomalies are favoured.
"The continuation of warmer-than-average sea surface temperatures in the Tasman Sea, as well as a central-based El Nino, may contribute extra warmth, moisture, and increased risk for occasional heavy rainfall events this autumn season, although long dry spells are forecast to begin the season."
He said nationwide, March-May 2019 temperatures were forecast to be above average (50-60% chance) for all regions of New Zealand.
"A particularly warm start is expected for the autumn season, but cold snaps and frosts are likely to occur in colder locations as the season progresses."
