Current Climate - April 2010

More frequent anticyclones (‘highs’) were located over and to the east of the North Island during April, resulting in a very dry month for much of the North Island and upper South Island. Drought was declared for Auckland, Waikato, Bay of Plenty, South Taranaki, South Canterbury and Otago in April, joining Northland which was declared a drought area in January. Even after some helpful rainfall at the end of the month, significant soil moisture deficits remain in many areas of the North Island (except for Taranaki, Gisborne, and the Kapiti Coast), as well as in Marlborough and Canterbury. In contrast, enhanced northwest winds affected the South Island, producing extraordinarily high rainfall in the southwest of the South Island.

Percentage of normal rainfall, April 2010.

End of month water balance in the pasture root zone for an average soil type, where the available water capacity is 150 mm.

Departure from average air temperature for April 2010.

Rainfall

Well below normal April rainfall (less than 50 percent of normal) occurred across most of the North Island, as well as in Nelson, Marlborough and north Canterbury.  Areas that received slightly more substantial rainfalls (between 50 and 80 percent of normal) included Taranaki, Gisborne, the Kapiti Coast, and south Canterbury. In comparison, it was an extraordinarily wet April in Fiordland, south Westland and parts of Southland, with more than double normal rainfall experienced there.  Rainfall was also above normal (more than 120 percent of usual) in Otago, but near normal in north Westland and Buller.

Air temperature

It was an extremely warm April for much of the South Island, the Wairarapa, eastern Northland and eastern Auckland, with temperatures more than 1.2°C above average.  In contrast, April temperatures were near average across the remainder of the North Island (within 0.5°C of the long-term average), as well as in Buller.  The New Zealand national average temperature was 14.2°C (+0.8°C above the long-term April average).

Sunshine

April was an extremely sunny month for the eastern North Island and Northland, with totals above 125 percent of normal. It was also rather sunny (between 110 and 125 percent of normal) in the Central Plateau, Bay of Plenty, Manawatu-Wanganui, Wellington, Marlborough and Canterbury.  It was a cloudy month for the West Coast, Southland and Otago, with below average sunshine (between 75 and 90 percent of normal).

See our April 2010 climate summary.

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