Climate

New Zealand Climate

Cold, sunny, and frosty

July was colder, sunnier, and more settled and frosty than average, with well below normal rainfall in most areas. July climate patterns were associated with more anticyclones (‘highs’) than average over New Zealand and in the Tasman Sea. As a result, winds were mostly light during the month, and there were low nighttime temperatures, and above average sunshine in most regions.

Record low rain

Parts of the central North Island had the lowest recorded July rainfall. Kawerau and Rotorua received less than 20% of normal rain. The north of the South Island had the driest July in at least 60 years, with just 10% of normal rain in Nelson and 15% at Blenheim Airport.

Snowfall

A very cold southerly outbreak brought significant snowfall to sea level in the eastern South Island on 4–5 July, with heavy snowfall settling to 300–500 m in the central and eastern North Island on the 5th. Severe overnight ground frosts followed for several days, especially in the South Island.

Relatively cool month

Mean and minimum temperatures were below average over much of New Zealand, although it was warmer than average in parts of inland and Central Otago. The July national average temperature of 7.3 °C was 0.4 °C below average. There were more ground and air frosts than usual in many areas, especially in the south and west of the North Island, the Central Plateau, and parts of the north and east of the South Island. Severe ground frost of -6.0 °C or lower occurred somewhere in New Zealand on most days of the month. Levin recorded 22 ground frost days, which was 10 more than normal.

Percentage of average rainfall for July 2003 (recording sites shown with dots). Click to enlarge.

Difference from the average air temperature in degrees Celsius for July 2003. Click to enlarge.