NIWA has published its climate outlook for the next three months:
“La Niña conditions for the rest of 2010”
The equatorial Pacific is now in a La Niña state, which is likely to continue until the end of the year.
Early spring temperatures look to be at, or just below, normal for much of the country, and cold snaps are still likely to occur.
Other than the lower half of the North Island, which will see below average rainfall, the rest of the country is likely to experience average rainfall.
Soil moisture is also likely to be near average for most of the country, with the West and East North Island likely to see some deviation from normal.
Sea level pressures are likely to be above normal near New Zealand.
Overall Picture
Temperature:
Early spring temperatures are likely to be near average or above average in all regions. However, short-term cold snaps and frosty periods typical of early spring will still occur. Sea surface temperatures are expected to be near average or above average around New Zealand over the August to October period.
Rainfall, soil moisture, and stream flows:
Rainfall is likely to be near normal in most places, but normal or below normal in the western North Island, and normal or above in the east of the North Island. Normal soil moisture levels and stream flows for August-October as a whole are likely in many regions, except for normal or below normal conditions in the west of the North Island, and normal or above normal soil moisture levels in the eastern North Island.
Regional predictions for the next three months:
Northland, Auckland, Waikato, Bay of Plenty:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall, soil moisture levels, and stream flows totals are likely to be near normal.
Central North Island, Taranaki, Wanganui, Manawatu and Wellington:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall totals, soil moisture levels, and stream flows are likely to be either normal or below normal.
Gisborne, Hawke’s Bay, Wairarapa:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall totals and soil moisture levels are likely to be either normal or above normal, while normal stream flows are likely.
Nelson, Marlborough, Buller:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall, soil moisture levels, and stream flows are likely to be near normal.
West Coast, Alps and Foothills, Inland Otago, Southland:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall soil moisture levels, and stream flows are likely to be near normal.
Coastal Canterbury, East Otago:
Temperatures are equally likely to be in the above average or near average range. Seasonal rainfall, soil moisture levels, and stream flows are likely to be near normal.
Background
The tropical Pacific has moved steadily towards La Niña conditions over the past few months, and is now in a La Niña state. La Niña conditions are likely to continue through the remainder of 2010.