Climate Update 37 - July 2002

July

Climate

River flows

Soil moisture

Three-month outlook

Checkpoint

Backgrounder

Backgrounder

Backgrounder

2002 rainfall to date
Rainfall so far this year has been lower than average across some central and eastern parts of the North Island. Much of the South Island has received normal or above normal rainfall. Parts of the north and west of the North Island have also been wetter than average.

Total rainfalls for 1 January to 30 June 2002, shown according to decile rankings of all rainfalls for this period from 1972.

Checkpoint

Outlook and outcome – April to June 2002

These Checkpoint maps differ from the print issue of The Climate Update, where a substitute map set was accidentally included during printing.

Rainfall was expected to be near normal in most regions and below normal in the east. The outcome was as expected in the North Island and most of the South Island. Parts of Southland and Otago received 125 -175% of normal.
Air temperatures were normal or above normal in all regions as predicted.
Normal river flows were expected for most regions of the country, except in the east.

July

Climate Update is a summary each month of New Zealand's climate, including soil moisture and river flows.
July 2002 – Number 37
June’s climate: The third warmest June on record was accompanied by floods and snow.
June’s river flows: June flows were above normal for most of the country.
Soil moisture levels: Above average rainfalls during June reduced or eliminated remaining root zone soil moisture deficits in most parts of the country.
Three month outlook: Generally warmer than average, but winter's typical cold outbreaks not ruled out.
Checkpoint: How well are we doing with

Climate

New Zealand Climate in June 2002
Hot, cold, wet, dry – June had it all
It was the third warmest June since records began in the 1850s. New Zealand’s national average temperature for the month was 9.8 °C, which was 1.5 °C above normal. Hamilton was 3.5 °C above normal, its warmest June since 1907.

Three-month outlook

The outlook for July to September 2002
The evidence for a developing El Niño event, which is expected to influence New Zealand climate over spring and summer 2002-03, continues to strengthen, though the magnitude of the coming event remains uncertain.
El Niño is typically associated with below average temperatures in many places. However, the outlook for July to September 2002 is for normal or above normal temperatures in all regions because of the influence of local sea temperatures and a warm Indian Ocean.

River flows

New Zealand River Flows in June 2002
June streamflows mostly high
June flows were above normal for most of the country, below normal around Gisborne and Hawkes Bay, and normal in Canterbury and much of Marlborough.

Soil moisture

Soil moisture on 30 June
Above average rainfalls during June reduced or eliminated remaining root zone soil moisture deficits in most parts of the country. Soils in a few areas of Gisborne, Hawke’s Bay, coastal Marlborough, and inland Otago were at less than field capacity at the end of the month.