Outlook and outcome – December 2004 to February 2005

Rainfall was as forecast in the north and southwest of the North Island, and in north Canterbury, Central Otago, and Southland. It was wetter than predicted elsewhere in the east, and lower than predicted elsewhere in the west.

Air temperatures were lower than forecast in parts of the North Island, but generally average or below average as predicted in the South Island.

Streamflows were normal to above normal in much of the North Island, apart from Hawke’s Bay and the east coast where they were below normal. Streamflows were below normal or normal in the north and west of the South Island and well above normal in the east and south.


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 December to February 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.