Current Climate - May 2010
May was a stormy month overall, with more lows than normal located in the Tasman Sea, and higher pressures east of the Chatham Islands. This produced more northeasterly winds than normal over New Zealand, resulting in an extremely wet month and several flood events in eastern regions. Soil moisture levels are now at capacity in most regions, but soils remain drier than normal in Waikato and Manawatu.
End of month water balance in the pasture root zone for an average soil type, where the available water capacity is 150 mm.
Rainfall
It was an extremely wet May in eastern regions of both Islands. Rainfalls were more than 200 percent (double) normal in Nelson, Marlborough, Canterbury and eastern Otago, Coromandel, Bay of Plenty, Hawkes Bay and coastal Wairarapa. Rainfall was also well above normal (more than 150 percent of normal) in eastern Northland and Auckland, and above normal (between 120 and 150 percent of normal) in Taranaki and Gisborne. In contrast, it was very dry on the West Coast, and in Fiordland and Southland, with less than 50 percent of normal rainfall recorded.
Air temperature
May temperatures were above average (between 0.5°C and 1.2°C above average) in Wairarapa, Nelson, Westland and Fiordland (showing the effects of the enhanced northeasterly winds), and around Christchurch. Temperatures were mostly near average elsewhere (within 0.5°C of the long-term average), except for small pockets of below average temperatures (between 0.5°C and 1.2°C below average) in eastern Otago. The New Zealand national average temperature was 11.3°C (+0.6°C above the 1971-2000 May average).
Sunshine
It was an extremely cloudy May for Nelson, Marlborough, coastal mid-Canterbury, Wellington and the Wairarapa. Sunshine totals were also below normal (between 75 and 90 percent of normal) in other parts of Canterbury, Taranaki, Bay of Plenty and Gisborne. In contrast, sunshine totals were above normal (between 110 and 125 percent of normal) for Westland, Fiordland, Southland, central North Island and Auckland.
See our May 2010 climate summary.
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