May's climate

New Zealand climate in May 2006

Rainfall (click to enlarge).

Temperature (click to enlarge).

May was very wet in parts of Northland and Auckland, and in coastal Canterbury. In contrast, well below normal rainfall was recorded in Central and East Otago.

May was warmer than average in much of the north and west of the North Island, and in Nelson and the west of the South Island, but cooler than average in parts of Wairarapa, South Canterbury, Otago, and Southland. The national average temperature of 11.0 °C was 0.3 °C above the 1971-2000 average.

For more information on the climate in May, visit the climate summaries page at www.niwascience.co.nz/ncc/cs/mclimsum_06_05

Soil near saturation

Soil moisture (click to enlarge).

Soil moisture levels at the end of May were near saturation in many areas of both the North and South Islands. Parts of coastal Marlborough and inland Otago remained drier than normal.

 

High river flows in the north and east

River flows (click to enlarge).

River flows were above normal in the north and east of the North Island, and the east of the South Island. River flows in the west and south of both islands were normal or below normal.

March 2006 to May 2006: the climate we predicted and what happened

(click to enlarge).

Rainfall

Rainfall was above normal in the north and central North Island, and normal or above normal as was predicted in the east. Conditions in the southwest of the South Island were drier than predicted; in the east, the predicted dry conditions ended abruptly in April.


(click to enlarge).

Air temperature

Air temperatures were above average as predicted in parts of the North Island, and average, as predicted, in much of Canterbury and Otago. Elsewhere conditions were mostly cooler than expected.


(click to enlarge).

River flows

Streamflows were above normal to normal in the north and east of both islands, and normal or below normal in the west and south of both islands.


The three outcome maps give the tercile rankings of the rainfall totals, mean air temperatures, and mean river flows that eventuated from March to May, in comparison with the forecast conditions.

As an approximate guide, middle tercile rainfalls typically range from 80 to 115% of the historical normal, and middle tercile temperatures range about the average by plus or minus 0.5 °C.