Summer 2012-13

Very dry for the North Island. An extremely sunny summer across the country. 

Rainfall

An extremely dry summer for much of the North Island.  Many North Island regions recorded rainfall totals around half of summer normal.  However, parts of Northland and north Auckland, the Bay of Plenty (including Taupo), Hawkes Bay and Wairarapa only received around one third of normal summer rainfall.  Also rather dry for Westland and Canterbury.  In contrast, wetter than usual for Marlborough and the Kaikoura coast, and around Mt. Cook.

Sunshine

Record high sunshine for regions south of Hamilton.

Temperature

Most regions experienced near average summer temperatures.  Above average temperatures for many inland and eastern parts of the North Island, and some eastern areas of the South Island.

Soil moisture

As at 1 March, extreme deficit (more than 130 mm of deficit) evident in Northland, Auckland, Waikato, the Bay of Plenty region (including Taupo), Gisborne, Hawkes Bay, Wairarapa, between Wanganui and Palmerston North, parts of Marlborough, Canterbury, and Central Otago. Significant deficit (more than 110 mm of deficit) generally observed elsewhere in the North Island, the Waimea Plains and eastern Otago. An adverse event due to drought was declared in Northland on 27 February.

Overview

Summer was characterised by much higher pressures than normal over the Tasman Sea and New Zealand region, with more southwesterly airflow than normal over the country. The frequent 'highs' over the country produced a very sunny summer for most of the country, and extremely dry conditions over most of the North Island. On 27 February, a state of drought was declared in Northland.

It was an extremely dry summer for much of the North Island. Many North Island regions recorded rainfall totals around half (50%) of summer normal. However, parts of Northland and north Auckland, the Bay of Plenty (including Taupo), and areas of the Hawkes Bay and Wairarapa only received around one third (33%) of normal summer rainfall. It was a record-dry summer for Whakatane, Taupo, Motu (Gisborne ranges), Masterton, and Waione (Tararua District). Other relatively dry regions included Canterbury and Westland, with below normal summer rainfall (between 50 and 70 percent of summer normal).

In contrast, South Taranaki through to Wellington experienced closer to normal summer rainfall, as did much of Otago, Southland and Fiordland. Marlborough and the Kaikoura Coast, as well the alpine area around Mt. Cook, experienced a wetter than usual summer.

As at 1 March 2013, extreme soil moisture deficit (more than 130 mm of deficit) was evident in Northland, Auckland, Waikato, the Bay of Plenty region (including Taupo), Gisborne, Hawkes Bay, Wairarapa, between Wanganui and Palmerston North, parts of Marlborough, Canterbury, and Central Otago. Significant soil moisture deficit (more than 110 mm of deficit) was generally observed elsewhere in the North Island, as well as the Waimea Plains, and across eastern Otago.

An adverse event due to drought was declared in Northland on 27 February.

It was an extremely sunny summer for much of the country (south of Hamilton), with numerous summer sunshine records broken. It was the sunniest summer on record for Te Kuiti, Turangi, New Plymouth, Dannevirke, Martinborough, Hokitika, Greymouth, Mt Cook, Cheviot, Ashburton, Lake Tekapo, Cromwell, and Balclutha.

Most regions experienced near average temperatures for summer, with mean temperatures within 0.5°C of summer average. However, parts of Auckland, Waikato, Bay of Plenty, Hawkes Bay, Wairarapa, coastal Canterbury, Otago, and Southland recorded mean temperatures between 0.5°C and 1.0°C above average, and much of the Central North Island recorded temperatures between 1.0°C and 1.5°C above summer average. The nation-wide average temperature in summer 2012/13 was 17.0°C (0.4°C above the 1971-2000 summer average), using NIWA's seven-station temperature series which begins in 1909.

Further highlights:

  • The highest summer temperature was 35.1°C, recorded three times during summer: at Clyde on 5 January, and at Gisborne on both 9 and 10 January.
  • The lowest temperature was -1.7°C, recorded at Motu on 1 December.
  • The highest 1-day rainfall experienced was 346 mm, observed at Mount Cook on 9 January.
  • The highest gust recorded was 206 km/hr at Cape Turnagain, on 2 December.
  • Of the six main centres in summer 2012/13, Auckland and Tauranga tied for the warmest, Tauranga was the sunniest, Christchurch was the driest, Wellington was the wettest, and Dunedin the coolest.

Full report

Summer 2012-13 climate summary (PDF 627 KB)

For further information, please contact:

Dr Richard Turner

Climate Modeller – NIWA National Climate Centre, Wellington

Tel. 04 3860315