Outlook and outcome – November 2002 to January 2003

Rainfall was near normal or below normal in many areas of the country as expected, but in the west and south of the South Island it was drier than predicted.

Air temperatures were expected to be near average for the North Island and the north of the South Island, and average or below average elsewhere. Temperatures were lower than expected over the North Island and were close to those predicted for the South Island.

River flows were higher than predicted over most of the North Island and the north of the South Island. They were lower than predicted in Westland. They were as expected in southwestern North Island regions, south and east South Island regions.

The outcome maps shown here give the tercile rankings of the rainfall totals and mean temperatures that eventuated for these months. Terciles were obtained by dividing ranked November to January data from the past 30 years into three groups of equal frequency (lower, middle and upper one-third values) and assigning the data for the present year to the appropriate group. (Click to enlarge)

As an approximate guide, middle tercile rainfalls often range from 80 to 115% of the historical average. Middle tercile air temperatures typically occur in the range of the average plus or minus 0.5°C.