Climate Summary for April 2014

Warm, with much needed rain for some regions

Rainfall 

April rainfall was near normal (within 20% of April normal) to above normal (120-150% of normal) for most of the country.  Additionally, there were many locations on both islands, chiefly the southern half of the North Island and the northern half of the South Island, which received well above normal rainfall (more than 150% of normal). In fact, some locations in the country received in excess of 300% of April normal rainfall.  In contrast, there were only a few locations that received below normal rainfall (50-79% of April normal), such as in Northland, Gisborne and Southland.

Soil moisture

As of 1 May 2014, soil moisture across the country had increased substantially when compared with March values for much of the North Island.  Of note are many locations on the North Island which have improved to near normal or wetter than normal soil moisture levels for the time of year.  In spite of the improved conditions, there still remains a sizeable area of abnormal dryness in parts of the Northland, Wanganui-Manawatu, Otago and Southland regions where soils are drier than normal relative to the time of year.

Temperature

April was unusually warm for most of New Zealand, in particular the North Island, where well above average temperatures (greater than 1.2°C above April average) were recorded for the month.  In fact, many reporting stations on the North Island placed in the top-four for warmest mean April temperatures, including several reporting stations in the Auckland region.  The warmth extended to the South Island where above average temperatures (0.5 to 1.2°C above April average) to well above average temperatures occurred.  Other regions in New Zealand experienced near average April temperatures (within 0.5°C of April average).

Sunshine

Below normal sunshine (75-89% of April normal) to well below sunshine (less than 75% of April normal) was recorded for the majority of the country.  However, regions from northern Waikato to Northland received near normal sunshine (within 10% of April normal) with a few spots in this area observing above normal sunshine (110-124% of April normal). There was also a thin section of the southern South Island that received near normal April sunshine.

Overview

April 2014 was characterised by higher pressure than normal to the southeast of New Zealand with lower than normal pressures over the Tasman Sea.  This pressure pattern resulted in north-easterly quarter wind flow anomalies for most parts of the country, with the exception of the north of the North Island, where lower pressures in the Tasman resulted in anomalous north-westerly airflows. 

In terms of rainfall, April featured a much welcome change for many areas of New Zealand, chiefly the North Island.  Many areas that were in desperate need of rain received above normal (120 to 150% of normal) or much above normal (more than 150% of normal) rainfall for the month.  This was echoed for a large part of the South Island, however there the rain was not so welcome for most locations.  This is particularly true for parts of the Tasman, Nelson, Canterbury and Marlborough regions where the wet April followed a wet March.  For some locations, the rainfall was exceptional compared to normal with three to five times the April normal falling at some of the aforementioned areas.

As noted above, the surplus of rain was quite beneficial for many as soil moisture levels across much of the North Island responded nicely.  For example, entering into the month of April soil moisture was considerably drier than normal.  However, in response to the described rainfall distribution, soil moisture levels at the beginning of May have recovered to levels much closer to normal, with some locations now observing wetter than normal soils for the time of year.  Having said that, there still remains regions of the North Island, chiefly about parts of Northland and northern Auckland, which have soil moisture levels that remain drier than normal.  Soils remain abnormally wet for this time of year from the Tasman east through the Marlborough regions and south into much of Canterbury region.

It was an abnormally warm month for a significant part of the country with much of the North Island experiencing mean temperatures well above average (more than 1.2°C above April average).  There were only a handful of locations on the North Island that experienced normal (within 0.5°C of April average) with no locations reporting below average temperatures (0.5 to 1.2°C below April average).  The South Island also experienced a warm April.  However, while well above average temperatures were common, especially for the west coast of the South Island, they were not as extensive for the island as a whole.  Still, outside of that area, above normal or normal temperatures were recorded for much of the South Island.  Unlike the North Island, there were a few isolated pockets of below normal mean temperatures observed for the month.  The nation-wide average temperature in April 2014 was 14.5°C (1.1C° above the 1971-2000 April average from NIWA’s seven station temperature series which begins in 1909).

With the abundant April rainfall came a lack of sunshine for much of the country as below normal sunshine (75 to 89% of April normal) to well below sunshine (less than 75% of April normal) was recorded for most of the country.  The sunshine was especially absent for the South Island where only the far southern part of the island managed to receive near normal values (within 10% of April normal).   Near normal sunshine was also restricted on the North Island and was limited to areas from the Waikato to Northland, with even a few splashes of above normal sunshine in these areas (110 to 124% of April normal).

Further Highlights

  • The highest temperature was 29.6°C, observed at Whakatane on 7 April.
  • The lowest temperature was -4.2°C, observed at Pukaki Aerodrome on 29 April.
  • The highest 1-day rainfall was 197 mm, recorded at Akaroa on 17 April. 
  • The highest wind gust was 146 km/hr, observed at Baring Head on 17 April.
  • Of the six main centres in April 2014, Auckland was the warmest and sunniest, Dunedin was the coolest and driest, Christchurch was the cloudiest and Wellington was the wettest.
  • Of the available, regularly reporting sunshine observation sites, the sunniest four centres so far in 2014 (January to April) are: Whakatane (1050 hours), Tauranga (947 hours), Auckland – Albany (913 hours) and Takaka (893 hours).

For further information

Please contact: 

Mr Chris Brandolino
Meteorologist – NIWA National Climate Centre
Tel. 09 375 6335

For climate data enquiries, please contact:

Mr Gregor Macara
Climate Scientist, NIWA Wellington
Tel. 04 386 0509

Download the full report 

NIWA National Climate Summary for April 2014 [721 KB PDF]

Climate statistics table

Climate statistics for April 2014 (PDF 64 KB)