January 2004

Temperatures: Warm, especially in the east
Rainfall: Dry in parts of Otago and Southland, the Christchurch area and central Marlborough; well above average rainfall in Wairarapa, Hawke’s Bay, Wellington, parts of Northland, the Southern Alps and North Otago
Soil moisture: Significant deficits in parts of eastern Otago, the Christchurch area and central Marlborough
Sunshine: Sunny in the north and east of the North Island, and the south of the South Island; less sunshine than normal in the southwest of the North Island
January was very warm overall, with above normal temperatures in mo

Temperatures: Warm, especially in the east

Rainfall: Dry in parts of Otago and Southland, the Christchurch area and central Marlborough; well above average rainfall in Wairarapa, Hawke’s Bay, Wellington, parts of Northland, the Southern Alps and North Otago

Soil moisture: Significant deficits in parts of eastern Otago, the Christchurch area and central Marlborough

Sunshine: Sunny in the north and east of the North Island, and the south of the South Island; less sunshine than normal in the southwest of the North Island

January was very warm overall, with above normal temperatures in most regions, especially in the east where it was very warm from Wairarapa to Southland. Continuing dry conditions occurred in parts of Otago and Southland, in the Christchurch area and central Marlborough, where soil moisture deficits are significant. However useful rainfall, particularly in the last week, brought relief to dry soils in Wairarapa, Northland, and other areas in the east of the South Island. Rainfall was well above average in parts of Northland, the Wairarapa, Hawke’s Bay, Wellington, the Southern Alps and parts of North Otago. Sunshine totals were above normal in the north and east of the North Island and in the south of the South Island. However, there was less sunshine than normal in the southwest of the North Island. The January climate patterns were associated with more frequent anticyclones (‘highs’) than usual to the north of the North Island, and to the far southeast of New Zealand, with lows in the western Tasman Sea. These produced more frequent easterlies over the North Island and northeasterlies over the South Island.

Highlights

  • The highest January 2004 temperature was 38.4°C, recorded at Darfield on the 1st; equal to the highest January temperature on record for the South Island, and second only to 38.9°C recorded in Ruatoria in the North Island on 11 January 1979. Hanmer Forest recorded 7 days between 1 and 17 January with maximum temperatures exceeding 30°C. The lowest temperature for the month was –0.2°C, recorded at Manapouri Airport on the 21st.
  • Significant rainfall and gale force southerlies occurred over the lower North Island between the 18th and 23rd, with heavy falls, totalling up to 100 mm in Wairarapa on the 20th. The severe gales and high seas resulted in the cancellation of fast-ferry sailings through Cook Strait for two days.
  • High rainfall totalling 150 to 200 mm occurred in parts of Northland on the 29-30th. Rainfall totalling 74 mm was measured at St Bathans (Otago) on the 30th, with reports of flash flooding in Wanaka.
  • Of the four main centres, Christchurch was the driest, and Auckland the sunniest and warmest. It was wet in Wellington and Auckland, and below average rainfall occurred in the other two centres. Temperatures were above average in all four centres. Sunshine hours were below normal in Wellington, and near normal in Auckland, Christchurch, and Dunedin.

Temperature

Mean temperatures were above normal over much of New Zealand, being 1.0 to 2.0°C above average in most eastern districts from Wairarapa to Southland. The January national average temperature of 18.3°C was 1.2°C above normal, the warmest since January 1999, and the 11th warmest January since reliable measurements commenced in the 1850s.

Rainfall

Rainfall was below average in parts of Otago and Southland, the Christchurch area including Bank’s Peninsula and central Marlborough. About twice the average January rainfall occurred in parts of Hawke’s Bay, Wairarapa, Wellington, the Southern Alps and parts of North Otago.

Sunshine

Sunshine totals were above normal in Auckland, Bay of Plenty, Gisborne, Hawke’s Bay, and Southland. Sunshine was below normal in Taranaki, Manawatu, and Wellington.

Warm, especially in the east

Mean temperatures were at least 0.5°C above normal over much of New Zealand, and 1.0 to 2.0°C above average in most eastern districts from Wairarapa to Southland. The national average temperature was 18.3°C, 1.2°C above normal.

Well above average January mean air temperatures were recorded at:

Location Mean temperature Departure from average (°C) Records began Comments
Chateau, Ruapehu 14.4 +1.9 1930 2nd highest
Ohakune 16.7 +2.0 1994 2nd highest
East Taratahi 19.8 +2.6 1973 2nd highest
Farewell Spit 19.3 +2.0 1971 3rd equal highest
Motueka 19.0 +1.5 1957 2nd equal highest
Nelson Airport 19.2 +1.5 1944 2nd equal highest
Blenheim Airport 19.8 +1.8 1941 2nd equal highest
Rangiora 18.1 +1.4 1965 2nd equal highest
Lincoln 18.3 +1.5 1881 Well above average
Dunedin Airport 16.7 +1.7 1963 2nd equal highest

Mean daily maximum temperatures were almost 4°C above normal in inland parts of Wairarapa, and 2 to 3°C above average in parts of central Marlborough and Otago.

Record high January mean daily maximum air temperatures were recorded at:

Location Mean daily maximum temperature Departure from average (°C) Records began Comments
East Taratahi 26.6 +3.5 1973 Highest
Dunedin Airport 23.6 +2.8 1963 Highest

Dry in Otago and Southland, the Christchurch area and Central Marlborough

Rainfall was 50 percent (half) or less of average in parts of Southland, the Christchurch area including Bank’s Peninsula and central Marlborough and 75 percent (three quarters) of average in the remainder of Southland, Otago, and Marlborough.

Record low January rainfall was recorded at:

Location January rainfall (mm) Percentage of normal Year Records began Comments
Lumsden 45 51 1986 Lowest

Well above average rainfall in Wairarapa, Hawke’s bay, Wellington, The Southern Alps and North Otago

Above well average rainfall occurred in parts of Northland, Hawke’s Bay, Wairarapa, Wellington, and the Southern Alps and North Otago, most with over 200 percent (twice) of average January totals in places. Rainfall was near average elsewhere.

High January rainfall was recorded at:

Location January rainfall (mm) Percentage of normal Year Records began Comments
Kaitaia 174 205 1986 3rd highest
Waione 174 238 1992 Highest
Castlepoint 115 249 1902 Well above average
East Taratahi 102 201 1973 Highest
Wellington Airport 125 205 1960 Well above average
Haast 512 252 1986 Highest
Tara Hills, Omarama 110 235 1950 Well above average

Sunny in the north and east of the North Island, and the south of the South Island, less sunshine than normal in the southwest of the North Island

Sunshine totals were at least 110 percent of normal in Auckland, Bay of Plenty, Gisborne, Hawke’s Bay and Southland. Sunshine was below normal in Taranaki, Manawatu, and Wellington.

High January sunshine was recorded at:

Location January sunshine (hours) Percentage of normal Year Records began Comments
Invercargill Airport 215 119 1932 Well above average

Low January sunshine was recorded at:

Location January sunshine (hours) Percentage of normal Year Records began Comments
New Plymouth Airport 207 85 1973 3rd equal lowest

January climate in the four main centres

Of the four main centres, Christchurch was the driest, and Auckland the sunniest and warmest. It was wet in Wellington and Auckland, and below average rainfall occurred in the other two centres. Temperatures were well above normal in all four centres. Sunshine hours were below normal in Wellington, and near normal in Auckland, Christchurch, and Dunedin.

Auckland a Wellington Christchurch c Dunedin
Jan. mean temp. (°C) 20.5 a 17.5 18.8 16.3
Dep. from normal (°C) +0.9 +0.6 +1.4 +1.1
Above average Above average Above average Above average

Jan. rainfall (mm) 110 b 112 26 40
% of normal 147 155 62 55
Above average Above average Below average Well below average

Jan. sunshine (hours) 238 a 205 218 179
% of normal 103 83 95 101
Near average Below average Near average Near average

a Mangere    b Mt Albert   c Christchurch Airport

Highlights and extreme events

  • The highest January 2004 temperature was 38.4°C, recorded at Darfield on the 1st; equal to the highest January temperature on record for the South Island, and second only to 38.9°C recorded in Ruatoria in the North Island on 11 January 1979. This and other high temperatures in January 2004 included:
    Location Daily maximum temperature (°C) Date of occurrence Records began Comments
    Darfield 38.4 1 Jan. 1939 Highest for January
    Woodbury 37.0 1 Jan. 1994 Highest for January
    Timaru Airport 36.1 1 Jan. 1962 Highest for January
    Winchmore 35.8 1 Jan. 1950 2nd highest for January
    Hororata 36.0 1-2 Jan. 1962 Highest for January
    Culverden 35.0 1-2 Jan. 1984 Highest for January
    Snowden 34.7 3 Jan. 2000 Highest for January
    Middlemarch 35.0 3 Jan. 2001 Highest for January
    Kerikeri EWS 30.3 9 Jan. 1982 Highest for any month
    Whangarei Airport 31.0 9 Jan. 1968 Highest for any month
    Whitianga Airport 30.3 12 Jan. 1991 Highest for January
    Waione 33.5 3 Jan. 1992 Highest for any month
    Castlepoint 32.2 3 Jan. 1973 Highest for any month
    East Taratahi 34.2 3 Jan. 1973 Highest for January
  • The lowest temperature for the month was –0.2°C, recorded at Manapouri Airport on the 21st.
  • A depression brought significant rainfall to the lower North Island from the 18th-23rd, with heavy falls, totalling 50 to 100 mm in Wairarapa on the 20th. The same weather system produced high winds in Hawke’s Bay (gusts to 109 km/h at Napier Airport on the 20th) and severe southerly gales through Cook Strait (with gusts to 174 km/h at Baring Head and 146 km/h at Brothers Island on the 21st). The severe gales and high seas resulted in the cancellation of fast-ferry sailings for two days.
  • High rainfall totalling 150 to 200 mm occurred in parts of Northland, especially Kaitaia, from the 29-30th. Rainfall totalling 74 mm was measured at St Bathans (Otago) and the 30th, with reports of flash flooding in the Wanaka.

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.

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