During the month of May, air pressure was lower than normal over and to the south-west of the South Island while higher than normal pressures existed to the northeast of the country. This pressure set up led to a prevalence of north-westerly wind flow throughout the month.
RainfallRainfall was well above normal (>149%) for large parts of the South Island. The exceptions were parts of central and eastern Canterbury were below normal (50-79%) and well below normal (<50%) rainfall was recorded. In the North Island, rainfall was well above normal in Taranaki and Manawatu-Wanganui as well as the western portion of the Wellington region. Well below normal rainfall was recorded along the coastal fringes of Gisborne, Hawke’s Bay and eastern Wellington.
TemperatureMay temperatures were well above average (>1.20°C) for the entire North Island as well as the majority of the South Island. Pockets of above average temperatures (+0.51°C to +1.20 °C) were observed in Marlborough, Nelson, Tasman, the West Coast and Southland. No locations observed average temperatures (-0.50°C to +0.50°C) or colder than average temperatures.
SunshineSunshine was below normal (75-89%) in the regions of Southland, the West Coast, Tasman, Manawatu-Wanganui and Taranaki. Above normal sunshine (110-125%) was recorded along the eastern portions of Gisborne, Hawke’s Bay and eastern Wellington. Sunshine was near normal in the regions of Waikato, Auckland and Northland.
Soil MoistureAs at 1 June 2016, soil moisture levels were below normal for the time of year for large parts of Gisborne, Hawke’s Bay, the Wairarapa as well as central and northern parts of Canterbury. Soil moisture levels for the remainder of the country were near normal for the time of year.