Outlook and outcome – March 2005 to May 2005

Rainfall was below normal as predicted in the north of the North Island, but wetter than expected in Bay of Plenty, eastern North Island, and in Marlborough. Much of the South Island was drier than predicted.

Air temperatures were higher in the north of New Zealand than indicated in the March to May forecast, although much of the South Island recorded near normal temperatures as expected.

River and streamflows were higher than forecast in the eastern North Island, and lower than expected in the north and northwest of the South Island.


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 March to May 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.