Widespread dryness and soil moisture deficit.
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Rainfall |
Record low rainfall for parts of Northland, Auckland, and the Bay of Plenty. Widespread dryness – with under a quarter of normal February rainfall observed around Taupo, in parts of Gisborne, Hawkes Bay, and on the West Coast South Island; and under a half of February normal rainfall experienced in most other regions. |
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Soil moisture |
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, as well as in the Waimea Plains, and across eastern Otago. An adverse event due to drought was declared in Northland on 27 February. |
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Sunshine |
An extremely sunny February, with many records broken. |
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Temperature |
Afternoon temperatures were well above February average, and morning temperatures generally below average, in most regions. |
Overview
February 2013 was characterised by anticyclones ('highs') which were slow moving over New Zealand. These highs, or anticyclones, kept rain-bearing weather systems such as lows and fronts away, resulting in an extremely dry and sunny February for many regions of the country.
February rainfall totalled less than 15 mm (and also less than 15 percent of February normal) in parts of Northland, Auckland, and the Bay of Plenty. It was the driest February on record for Leigh (north Auckland), and Milford Sound. In the case of Leigh, it was also the driest month (of any month) in records which began in 1966.
The dryness was widespread. Rainfall was less than 25 percent, or a quarter, of February normal around Taupo, in parts of Gisborne and Hawkes Bay, and along the West Coast of the South Island. Less than half (50 percent) of normal February rainfall was generally observed across the remainder of the country. The exceptions were between Wanganui and Wellington, in Central Otago and the Lakes District (with near normal rainfall); and Marlborough and the Kaikoura coast (with rainfall between 50 and 80 percent of February normal).
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 in the Waimea Plains, and across eastern Otago. An adverse event due to drought was declared in Northland on 27 February.
The dominance of high pressures during February resulted in an extremely sunny month across New Zealand. Sunshine totals were well above normal (exceeding 125 percent of February normal) across most of the North Island (south of Auckland), on the West Coast South Island, along the Southern Alps, as well as north Canterbury and the Kaikoura coast. Elsewhere, sunshine totals were also above normal (between 110 and 124 percent of February normal). It was the sunniest February on record for numerous locations across both Islands. Notably, Wellington and Hamilton recorded their sunniest February on record, Tauranga experienced its second sunniest February, Christchurch observed its third sunniest February, and Dunedin recorded its 5th sunniest February.
Mean temperatures in February were above average (between 0.5°C and 1.2°C above the February average) across the west and south of the South Island, as well as in inland regions of the North Island. In contrast, below average February temperatures (between 0.5°C and 1.2°C below the February average) were observed around the Kaikoura Coast, as well as the east coast of the North Island. Elsewhere, mean temperatures were near average (within 0.5°C of the February average). The nation-wide average temperature in February 2013 was 17.1°C (0.2°C below the 1971-2000 February average), using NIWA's seven-station temperature series which begins in 1909.
Notably, however, in most regions, afternoon temperatures were typically well above February average, and morning temperatures below February average, due to the clear skies and relatively light winds associated with the prevailing high pressures.
Further Highlights:
- The highest temperature was 34.6 °C, recorded at Alexandra on 1 February.
- The lowest temperature was -1.1°C, observed at Mount Ruapehu on 6 February.
- The highest 1-day rainfall was 278 mm, recorded at North Egmont on 4 February.
- The highest wind gust was 145 km/hr, at Southwest Cape, Stewart Island, on 10 February.
- Of the six main centres in February 2013, Wellington was the sunniest but also the wettest; Auckland the warmest, Dunedin the coolest, and Christchurch the driest.
- Of the available, regularly reporting sunshine observation sites, the sunniest four centres so far in 2013 (January and February) are New Plymouth (634 hours), Whakatane (608 hours), Lake Tekapo (606 hours) and Tauranga (575 hours).
Full report
Full details of the February 2013 climate summary (PDF 618 KB)
Climate statistics table
Climate statistics for February 2013 (PDF 90 KB)
For further information, please contact:
Ms Georgina Griffiths
Climate Scientist - NIWA National Climate Centre, Auckland
Tel 09 375 4506
Mobile 027 293 6545