Outlook - July to September 2012
Neutral ENSO conditions presently exist in the tropical Pacific, but an El Niño is likely by spring if present warming rates continue. For late winter, there is inconsistency in the predicted pressure patterns, and it appears likely that there will be a transition from the more 'blocked' north-easterly anomalies persisting from the recent La Niña towards a zonal westerly flow at the end of the season as El Niño conditions settle in. Sea temperatures around New Zealand are likely to be near normal for the season as a whole. Late winter temperatures are likely to be near average overall for all regions except the west and south of the South Island, where average or above average temperatures are likely. Frosts and snowfalls typical of winter and early spring will occur from time to time. Rainfall is likely to be normal in the North Island, and normal or below in the South Island.
Late winter rainfall totals are likely to be near normal in the north and west of the North Island, and normal or below normal in all other regions. Soil moisture levels are likely to be normal or below normal in the north and east of the South Island, and near normal elsewhere. River flows are likely to be below normal in eastern South Island, normal or below normal for Nelson/Marlborough, and near normal in other regions of New Zealand.
Late winter temperatures are likely to be near average overall for all regions except the west and south of the South Island, where average or above average temperatures are likely. Frosts and snowfalls typical of winter and early spring will occur from time to time.