Outlook: July – September 2017

July – September 2017 temperatures are about equally likely to be above average (45% chance) or near average (40% chance) for the west and east of the North Island. In all remaining regions of New Zealand, above average temperatures for July – September 2017 as a whole are very likely (60-70% chance). Nevertheless, frosts and cold snaps will occur during the winter and early spring seasons. Coastal waters around New Zealand are forecast to remain above average and may warm further over the next three month period.

July – September 2017 rainfall totals are about equally likely to be near normal (40% chance) or above normal (35% chance) in the east of the North Island. For all remaining regions of New Zealand, rainfall totals are most likely to be near normal (40-50% chance) over the next three month period. In contrast to long periods of settled conditions during June, the first half of July may have more active, rainier intervals across New Zealand.

July – September 2017 soil moisture levels and river flows are about equally likely to be near normal (35-40% chance) or below normal (35% chance) in the north of the North Island and the north and east of the South Island. In the west of the South Island, soil moisture levels and river flows are both most likely to be in the below normal range (50% chance). Soil moisture levels and river flows are equally likely to be near normal (35% chance) or above normal (35% chance) in the east of the North Island. In the west of the North Island, soil moisture levels and river flows are most likely to be in the near normal range (45% chance). 

Graphical representation of the regional probabilities, Seasonal Climate Outlook, July-September 2017.
Research subject: Climate