Middlemarch recorded its second-highest March temperature when the mercury hit 31.8°C on March 2; and Clyde also recorded its second-highest March temperature (32.6°C) on the same day, which was the country’s highest March temperature.
But by March 10, a major change in the weather resulted in Middlemarch recording its third-lowest March temperature when it dipped to -2.6°C.
Oamaru also recorded its third equal-lowest temperature when it dropped to 1.3°C on March 16.
Record mean minimum air temperatures for March were also recorded at Cromwell (5.3°C) and (Clyde 4.8°C).
Dunedin’s March temperature was also below average with 13.0°C — down nearly 1°C.
More than 25 locations experienced record-breaking or near-record low mean temperatures for the month — the lowest being -4.9°C, on March 16, at Waipara in North Canterbury.
Milford Sound posted the country’s highest one-day rainfall when 117mm fell on March 25.
Overall, above normal rainfall was observed in parts of Fiordland and Southland.
By the end of March, soil moisture levels were lower than normal for much of the central and eastern regions of the South Island, and above average in the southern South Island.
Niwa analytical meteorologist Tristan Meyers said frequent cold fronts in March led to unusually chilly and windy weather, bringing the nationwide average temperature down to 14.8°C.
"Since the start of 2014, there have only been eight months during which the nationwide mean temperature was below average — or 8 out of a possible 123 months.
"The chilly month was driven by a double-barrel low pressure anomaly south and east of New Zealand, working in tandem with a high pressure area in the Tasman Sea, to produce a southwesterly wind flow anomaly across the country.
"The pattern was a result of a stronger-than-normal and northerly displaced polar jet stream.
"The sub-tropical jet was also positioned north of its climatological position, which meant that tropical air masses were largely absent from New Zealand."
He said the pattern was consistent with a "waning El Nino event" in the equatorial Pacific Ocean.
