March 2002

Monday, 1 April 2002

Very dry in many eastern regions Sunny almost everywhere Near average temperatures for most regions

In contrast to summer, low rainfall, especially in eastern regions, along with sunny conditions almost everywhere, were the main features of the climate during March.

It was very dry in the east from Gisborne to Otago, including Bay of Plenty, Taupo and Nelson, where many sites recorded 50 percent (half) or less of their normal March rainfall. Gisborne Airport’s March rainfall was only 12 mm, the 3rd equal lowest there for March in more than 95 years. A mere 8 mm was recorded at Lauder and 14 mm in Ettrick in Central Otago. Rainfall was also below normal in the east of Northland, Coromandel, parts of Taranaki, Wanganui, Wellington, parts of Nelson and Marlborough. Significant soil moisture deficits in Otago have now spread to parts of inland south Canterbury. Moderate deficits exist in Gisborne, Wairarapa, central Marlborough and the Canterbury Plains.

Almost all New Zealand locations experienced more sunshine than normal, following the rather cloudy summer. It was especially sunny in Buller, Nelson, and the east coast of the South Island.

The month was warmer than normal in Northland, Auckland, Waikato, Gisborne, Hawke’s Bay, Buller and Central Otago. Cooler than normal conditions prevailed in parts of King Country and Fiordland. Mean temperatures were near or slightly above normal elsewhere. The national average temperature of 16.1°C was 0.2°C above the mean March temperature for the period 1961–1990.

March’s climate pattern was dominated by many more often deep depressions (‘lows’) than usual over the seas south of New Zealand. These resulted in more frequent westerly winds than usual over the whole of New Zealand.

Very dry in many eastern regions

Rainfall was 50 percent or less than normal in many eastern regions from Gisborne to Otago, including Bay of Plenty, Taupo and parts of Nelson, and less than 75 percent of normal throughout parts of Northland, Coromandel, parts of Taranaki, Wanganui, Wellington and Marlborough.

Near or record low March rainfall was recorded at:

Location	March rainfall (mm)	Percentage of normal	Year Records began	Comments
Hicks Bay	25	23	1991	Lowest
Gisborne Airport	12	12	1905	3rd lowest
Lauder	8	11	1982	4th lowest
Ettrick	14	21	1985	2nd lowest
Chatham Islands	18	25	1951	Lowest

Rainfall was between 120 and 160 percent of normal in parts of Auckland, Buller, Nelson Lakes, the Southern Alps and coastal Southland, and near average elsewhere.

Sunny almost everywhere

Sunshine and solar radiation totals were above 110 percent of average throughout most of New Zealand, and at least 120 percent of average in Buller, Nelson, and the east of the South Island in Canterbury and Otago. Near or record high March sunshine hours were recorded at:

Location	March Sunshine (hours)	Percentage of average	Year Records began	Comments
Whakatane	228	113	1957
Nelson Airport	261	129	1949	2nd highest
Christchurch Airport	227	135	1949	Equal highest

Near average temperatures for most regions

Mean temperatures were about 1.0°C above normal in Gisborne and Hawke’s Bay, and at least 0.5°C above average in Auckland, Waikato, western Bay of Plenty, Wanganui, Wellington, Central Otago and parts of Northland. However, they were about 0.5°C below average in King Country and Fiordland. Mean temperatures were near average elsewhere.

Mean daily maximum temperatures were about 1.5°C above average in parts of Central Otago.

Highlights

Extreme temperatures

• The highest air temperature for the month was 31.9°C, recorded at Whakatu on 21 March. This was the highest March air temperature at Whakatu since measurements began in 1983.
• The lowest air temperature for the month was –1.5°C, recorded at Hanmer Forest on 23 March. The lowest March air temperature on record at Hanmer Forest is –3.3°C.

Thunderstorms

• A ferocious rainstorm on 1 March produced 98 mm between 3.05 and 4.05 pm in Egmont Village. This caused serious flooding and car accidents in North Taranaki. Inglewood recorded 59 mm between 3.15 and 4.15 pm on the same day.
• Thunderstorms were relatively frequent on the West Coast, occurring on 1–3, and 16–22 March. They also occurred in Southland on 1–3 March, Nelson 19–21 March, and Wellington on 21 March.

For further information, please contact:

Dr Jim Salinger – Principal Scientist, Climate NIWA National Climate Centre – Auckland Phone +64 9 375 2053 [email protected]

Stuart Burgess – Climatologist NIWA National Climate Centre – Wellington Phone +64 4 386 0569 [email protected]

Geoff Baird – Communications Manager Phone +64 4 386 0543 [email protected]

Acknowledgement of NIWA as the source is required.