Checkpoint

Outlook and outcome – September 2004 to November 2004

Rainfall was normal to below normal in the north and east of the North Island, as predicted. Higher rainfalls than forecast occurred in the west and southwest of the South Island, and it was drier than predicted in the northeast of the South Island.

Air temperatures were lower than predicted in Waikato, and in the east of the North Island and north of the South Island.

Streamflows were below normal in the northern North Island, and normal in the southwest of the North Island, as predicted. Lower flows than predicted occurred in some catchments in the west of the South Island. Flows were normal or below normal in other locations.

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 September to November 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.