Current climate – April 2015
April 2015 was characterised by air pressures which were higher than normal to the northeast of New Zealand and south of Australia. This pressure pattern resulted in a weak north-westerly flow anomaly across the North Island and a weak south-easterly flow anomaly over the South Island. The northward retreat of the subtropical belt of anticyclones allowed numerous fronts to pass over the country during the month, and these delivered bouts of heavy rain to many parts.
Rainfall
Rainfall was well above normal (> 149%) or above normal (120-149%) for southern, central and western parts of the North Island, western and northern parts of the South Island, and eastern and inland parts of Canterbury south of Christchurch. Rainfall was well below normal (< 50%) or below normal (50-79%) for Northland, Gisborne, northern Hawke’s Bay and coastal North Canterbury.
Temperature
April temperatures were above average (+0.51°C to +1.20°C) for most parts of the country. It was a particularly warm month for West Coast, eastern parts of Canterbury, Kapiti Coast, Manawatu-Whanganui and Taranaki where temperatures were well above average (> +1.20°C).
Sunshine
It was a sunny month for Northland and Dunedin where April sunshine was above normal (110-125% of the April normal). Remaining parts of the country weren’t so lucky, and received either near normal (90-109% of the April normal) or below normal (75-89% of the April normal) sunshine.
Soil Moisture
As of 1 May 2015, soil moisture levels were above normal for this time of year for parts of Waikato, Taranaki, Manawatu-Whanganui, eastern Mid-Canterbury, the Mackenzie Country and western Southland. Soil moisture levels were below normal for this time of year for eastern and northern parts of the North Island, and eastern parts of North Canterbury.