Retrospective: January-March 2017 Outlook

The combination of ENSO-neutral conditions, along with the absence of other large-scale climate drivers for the remainder of summer into early autumn, was expected to result in only weak air flow anomalies. Mostly typical summer conditions were expected with high pressure systems crossing the North Island and prevailing westerly winds over the South Island. Actual pressures lower than normal across New Zealand and south of the country. This pressure set up resulted in slightly more westerly winds than normal.

Predicted air temperature: January – March 2017 temperatures were equally likely to be near average or above average for the north and east of the North Island and for the east of the South Island.  Near average temperatures were most likely for the remainder of the country.

Outcome: Actual temperatures were above average in the Bay of Plenty, Gisborne and Hawke’s Bay as well as the districts of Whangarei and Thames-Coromandel. Temperatures were largely near average for the remainder of the North Island. In the South Island, temperatures were near average for most with pockets of below averages temperatures recorded in parts of Southland and eastern Otago.

Predicted rainfall: January – March 2017 rainfall totals were forecast be near normal or below normal for all North Island regions and for the north of the South Island. Near normal rainfall was most likely for the east and west of the South Island.

Outcome: Actual rainfall was above normal for Auckland, the Bay of Plenty and northern Waikato as well as parts of Northland, Wellington and Hawke’s Bay. Rainfall was near normal for the remainder of the North Island. In the South Island rainfall was largely near normal. The exceptions were western Tasman, Waitaki and Dunedin where above normal rainfall was observed.