NATIONAL CLIMATE SUMMARY – FEBRUARY 2001
A MONTH WITH DRAMATIC CONTRASTS
- INCREDIBLY DRY IN THE CENTRAL AREAS, UNUSUALLY WET IN THE NORTH
•{\f "Symbol" \s 10} SEVERE SOIL MOISTURE DEFICITS CONTINUE IN THE NORTH AND EAST OF THE SOUTH ISLAND AND LOWER NORTH
ISLAND
EXTREMELY WET IN BAY OF PLENTY AND COROMANDEL
•{\f "Symbol" \s 10} WARM IN MANY REGIONS
•{\f "Symbol" \s 10} SUNNY IN CENTRAL NEW ZEALAND
A continuation of severe soil moisture deficits in Marlborough, Nelson, Canterbury and Wellington, with extreme or very
high fire risk were features of climatic conditions in these regions during February. Severe soil moisture deficits now
extend from Nelson through to North Otago in the South Island, and have spread to the Wairarapa in the North Island. In
contrast, unusually high rainfall created significant runoff throughout Bay of Plenty, as well as parts of Gisborne and
Waikato.
Marlborough, Nelson and Canterbury rainfalls were much less than 25 percent of normal in many areas. Blenheim’s 2-month
rainfall total was only 8 mm; the 2nd lowest for any January through February period there in records going back to
1930. Only 1939 was drier. It was also very much drier than average in Buller, north Otago and Wellington, with rainfall
50 percent (half) or less than normal. Rainfall was below average over the entire South Island.
The wet unsettled weather throughout coastal Bay of Plenty and Coromandel, resulted in rainfall totals ranging from 200
to over than 400 percent of normal there. It was also unusually wet for the Chatham Islands. Other wetter than average
regions were Auckland, Waikato, King Country, Tongariro, Gisborne and Hawke’s Bay.
February was a warm month in many areas, with mean temperatures between 0.5 and 1.5°C above normal over much of the
North Island, as well as northern and inland South Island areas, including the Kaikoura and Canterbury coasts. In
contrast, mean temperatures were between 0.5 and 1.0°C below average on the west coast of the South Island. The national
average temperature was 17.7°C, which was 0.6°C above the 1961 – 1990 normal. Sunshine totals were above average
throughout in central New Zealand, but below average totals occurred in Bay of Plenty, Gisborne and Hawke’s Bay.
February’s climate patterns were due to more frequent anticyclones (‘highs’) centred in the Tasman Sea and the east of
New Zealand, maintaining ridges across central New Zealand. These caused the very dry conditions over the middle of the
country. Lower than average pressures prevailed north of the North Island giving more prevalent easterlies in northern
North Island regions, drawing in warm and humid air masses from the tropics at times and producing rather wet
conditions.
EXTREMELY DRY IN MARLBOROUGH, NELSON AND CANTERBURY
Rainfall was extremely low in Marlborough, Nelson, Canterbury and Buller, with totals much less than 25 percent of
normal in many areas. It was also very much drier than average in Buller, north Otago and Wellington, with rainfall 50
percent (half) or less than normal. Other drier regions, with less than 75 percent of normal rainfall, were southern
Wairarapa, parts of Taranaki, Westland, Fiordland, Central and eastern Otago and much of Southland.
Near or record low February rainfall was recorded at
Westport 39 mm , 28% of normal, lowest on record which began in 1945
Lake Rotoiti 7 mm, 7% of normal, lowest in record, which began in 1934
Motueka. 2 mm, 3% of normal, 2nd lowest, records began in 1943
Nelson Airport 6 mm, 11% of noraml, 3rd lowest of records back to 1941
Blenheim Airport, 3 mm, 9% of normal. 4th lowest in records back to 1941
Hanmer Forest 7 mm, 10% of normal, 2nd lowest in records back to 1905
Christchurch Airport, 4 mm, 10% of normal. Lowest in records back to 1944
Christchurch Gardens 4 mm, 10% of normal, 3rd lowest in records back to 1864
Timaru Airport 9 mm, 19% of normal, lowest in records back to 1957
Waimate 10 mm, 20% of normal, lowest in records back to 1898
Manapouri 15 mm, 19% of normal, 3rd lowest in records back to 1914
EXTREMELY WET AND UNSETTLED IN BAY OF PLENTY AND COROMANDEL
February’s rainfall was unusually high throughout coastal Bay of Plenty and Coromandel, with totals ranging from 200 to
more than 400 percent of normal. In Coromandel, some locations had seven more rain days than the February normal. It was
also unusually wet for the Chatham Islands. Other wetter than average regions were Auckland, Waikato, King Country,
Tongariro, Gisborne and Hawke’s Bay, all having at least 125 percent of normal rainfall.
Extremely high February rainfall was recorded at:
Great Barrier Island, 212 mm, 277% of normal, 2nd highest on records back to 1977
Whitianga, 270 mm, 281% of normal,, 2nd highest on record back to 1942
Tauranga Airport 268 mm, 325% of normal, 2nd highest on record back to 1898
Te Puke 263 mm, 228% of normal, 3rd highest on record back to 1973
Whakatane 310 mm, 426% of normal, highest on record
Chatham Islands 115 mm, 207% of normal, 3rd highest on record back to 1957
WARMER IN THE NORTH ISLAND AND NORTHERN AND INLAND SOUTH ISLAND
Mean temperatures ranged from 0.5 to 1.5°C above normal over much of the North Island, as well as northern and inland
South Island areas, including the Kaikoura and Canterbury coasts.
Extremely high February mean temperatures were recorded at
Tauranga Airport 20.7°C, +1.6 above normal, 2nd highest
Taupo Airport 18.5°C, +1.8 above normal, 3rd highest
It was much cooler than average, with mean temperatures between 0.5 and 1.0°C below normal, on the west coast of the
South Island.
SUNNY IN CENTRAL NEW ZEALAND
Sunshine and solar radiation totals were at least 110 percent of normal in Wellington, Marlborough and Nelson. Sunshine
totals were well below average in Bay of Plenty, Gisborne and Hawke’s Bay with totals less than 80 percent of normal.
Near normal sunshine occurred elsewhere.
HIGHLIGHTS
Extreme temperatures
The highest air temperature for the month was 35.3oC, recorded at Timaru Airport on the 4th. The highest February air
temperature on record for this location is 39.8°C.
The lowest air temperature for the month was –2.8oC, recorded at Ranfurly on the 7th after a clearance from cold
southerly conditions. The lowest February air temperature on record for this location is -3.1°C.
High rainfall
High rainfall occurred in Coromandel on the 11th, with totals as high as 120 mm recorded at Whitianga, and at least 50
mm throughout much of eastern Northland, Bay of Plenty, Waikato and Wanganui. Further high rainfall occurred in Bay of
Plenty and Gisborne on the 17th, Whakatane recording 130 mm.
For further information, please contact:
Dr Jim Salinger, NIWA - Auckland,
Tel (09) 375 2053 (Business) or (09) 527 3939 (after hours)
© Copyright NIWA 2001. All rights reserved.
ENDS