Winter 2003
Tuesday, 9 September 2003
Rainfall: Generally drier than normal, with well below average rainfall in Bay of Plenty and the eastern South Island; above average in Fiordland
Temperatures: Above average in most regions; 10th equal warmest winter on record
Sunshine: Well above average in Wellington and coastal Otago
The winter of 2003 was warmer and drier than usual. It was much warmer than normal in inland sheltered areas of Canterbury and Otago. This was, in part, mainly due to an extremely warm June, in fact the warmest on record for New Zealand overall. July was colder, sunnier, drier, and frostier than average in many areas, with a severe snowstorm which swept the country early in the month. Well below average winter rainfall was also a feature in the eastern South Island and Bay of Plenty. August was much drier than average in many inland and western regions, with colder or wetter than usual conditions in some areas exposed to the east. Many areas experienced near or above average winter sunshine hours. The winter’s climate patterns were dominated by many more anticyclones (‘highs’) well to the east of the South Island with more frequent northwesterlies over southern New Zealand and above average pressures elsewhere.
Highlights:
- Winter 2003 temperature extremes ranged from a high of 22.3°C recorded at North Clyde, Wairoa on 6 June to a low of –14.8°C, recorded at Tekapo on 13 July.
- Severe overnight ground frosts occurred in many eastern South Island areas after 10June, with –15.9°C recorded in Mt Cook Village on the 18th. Severe ground frosts of –10 to –12C° occurred in several inland areas of Canterbury and Otago on 24 July.
- Five heavy rainfall events occurred, the most severe occurring in the Nelson/Golden Bay region.
- Significant snowfall occurred to sea level in the eastern South Island on 4–5 July, with heavy snowfall settling down to 300–500 m in the central and eastern North Island on the 5th. Cold southeasterlies also brought snowfall settling down to 400–500 m in Canterbury and Otago from the 11–13 and 20–22July.
- Christchurch and Dunedin were the driest of the four main centres, with only about half of the normal rainfall. Christchurch was the sunniest. Winter rainfall was below average in all the main centres. Mean temperatures were above average in Auckland and Wellington by almost 1°C, and also above average in Christchurch and Dunedin. Sunshine hours were well above average in Wellington and Dunedin, and near average in the other two centres.
Rainfall
Rainfall was well below average in inland Bay of Plenty, and some coastal areas of Canterbury and Otago. It was also drier than normal in Taupo Ruapehu/Tongariro, and much of Marlborough and inland Canterbury. The winter was wetter than average in Fiordland and scattered areas of coastal Southland.
Temperatures
Mean temperatures were well above average in inland sheltered areas of Canterbury and Otago, where the winter, overall, at many sites was the warmest on record (due to the extremely warm June). It was also warmer than average overall in most other regions. The winter national average temperature was 8.9°C (0.6°C above normal). This was the 10th equal warmest (all of which have occurred after 1961) since measurements commenced in the 1850s.
Sunshine
Sunshine was well above average in Wellington and coastal Otago. It was also sunnier than normal in Hawke’s Bay, Nelson, Westland, and Southland. Totals were near normal in most other regions.
Below average rainfall in Bay of Plenty and the eastern South Island, above average rainfall in Fiordland
Rainfall totals were well below average, being less about 50 percent (half) of normal in inland Bay of Plenty, and some coastal areas of Canterbury and Otago. Rainfall was less than 75 percent (three quarters) of normal in Taupo Ruapehu/Tongariro, and much of Marlborough and inland Canterbury. Totals were about 125 percent (one and a quarter) of normal in Fiordland and scattered areas of coastal Southland.
Low winter rainfall was recorded at:
| Location | Winter rainfall (mm) | Percentage of normal | Year records began | Comments |
|---|---|---|---|---|
| Kawerau | 297 | 57 | 1954 | Well below average |
| Rotorua Airport | 211 | 51 | 1964 | 3rd lowest |
| Rangiora | 99 | 58 | 1965 | Well below average |
| Christchurch Airport | 92 | 52 | 1944 | Well below average |
| Christchurch Gardens | 98 | 50 | 1864 | Well below average |
| Le Bons Bay | 138 | 44 | 1984 | Lowest |
| Timaru Airport | 49 | 40 | 1957 | Well below average |
| Dunedin, Musselburgh | 106 | 54 | 1918 | Well below average |
Above average temperatures overall
Mean temperatures were at least 1.0°C above average in inland sheltered areas of Canterbury and Otago, where the winter, overall, at many sites was the warmest on record. Temperatures were at least 0.5°C above average in most other regions. However, they were near average in Buller, and coastal areas of both south Canterbury and Otago.
Near or record high mean winter temperatures were recorded at:
| Location | Mean temperature | Departure (°C) | Records began | Comments |
|---|---|---|---|---|
| Farewell Spit | 11.0 | +1.6 | 1971 | Highest |
| Mt Cook Village | 4.6 | +1.7 | 1929 | 3rd highest |
| Tara Hills, Omarama | 4.3 | +1.7 | 1950 | Highest |
| Queenstown | 6.1 | +1.3 | 1872 | Highest |
| Lauder | 4.6 | +1.1 | 1981 | Highest |
Much sunnier than average in Wellington and coastal Otago
Sunshine hours were well above average (at least 120 percent of normal) in Wellington and coastal Otago, and at least 110 percent of normal in Hawke’s Bay, Nelson, Westland, and Southland. Totals were near normal in most other regions.
Near or record high winter sunshine hours were recorded at:
| Location | Winter sunshine (hours) | Percentage of normal | Year records began | Comments |
|---|---|---|---|---|
| Wellington, Kelburn | 406 | 121 | 1928 | Well above average |
| Dunedin, Musselburgh | 379 | 126 | 1948 | 4th highest |
Winter climate in the four main centres
Of the four main centres, Christchurch and Dunedin were the driest, receiving 92 and 106 mm respectively, being only about half of the normal rainfall. Christchurch was the sunniest. Winter rainfall was below average in all the main centres. Mean temperatures were above average in Auckland and Wellington by almost 1°C, and above average in Christchurch and Dunedin by about 0.5°C. Sunshine hours were well above average in Wellington and Dunedin, and near average in the other two centres.
| Aucklanda | Wellington | Christchurch | Dunedin | |
|---|---|---|---|---|
| Winter mean temp. (°C) | 12.0 | 9.9 | 7.6 | 7.5 |
| Dep. from normal (°C) | +0.9 | +0.9 | +0.6 | +0.4 |
| Above average | Above average | Above average | Above average | |
|
|
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| Winter rainfall (mm) | 322 | 358 | 98 | 106 |
| % of normal | 77 | 86 | 50 | 54 |
| Below average | Below average | Below average | Below average | |
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| Winter sunshine (hours) | 405b | 406 | 417 | 379 |
| % of normal | 104 | 121 | 108 | 126 |
| Near average | Well above average | Near average | Well above average | |
a Mt Albert, b Estimated for Whenuapai
Highlights
- Winter 2003 temperatures ranged from a high of 22.3°C recorded at North Clyde, Wairoa on 6 June to a low of –14.8°C, recorded at Tekapo on 13July. This was Tekapo’s 2nd equal lowest July air temperature on record (measurements started 1925).
- June was the warmest on record in New Zealand, with mean temperatures very much above average in most places, and 3.0°C or more above average in inland sheltered areas of the eastern South Island.
- Severe overnight ground frosts occurred in many eastern South Island areas after 10June, with –15.9°C recorded in Mt Cook Village on the 18th. Christchurch Airport recorded grass minima of –10.4°C on the 17th, and –10.7°C on the 26th, both breaking the previous all time record there, in measurements that began in 1954. Severe overnight ground frosts occurred at Ettrick (–12.2°C) on 14 July, and –10 to –12C° in several inland areas of Canterbury and Otago on 24July.
- High rainfall occurred in Manawatu and Nelson on 3June, and was widespread over much of the North Island over the 8th and 9th (with surface flooding in Auckland and Hamilton) and again between the 15th and 17th. Floods and land slips occurred in the Golden Bay–Nelson region during high rainfall (100 mm or more) over the 28th and 29th (207 mm at Takaka and 170 mm at Appleby). High rainfall occurred in Wellington on 30June, with surface flooding in places. Heavy rainfall occurred in Northland, Coromandel and along the southern Wairarapa coast over 21–22 August.
- High winds associated with a tornado resulted in property damage in Greymouth on 17June.
- A very cold southerly outbreak brought significant snowfall to sea level in the eastern South Island on 4–5 July, with heavy snowfall settling down to 300–500 m in the central and eastern North Island on the 5th. Severe overnight ground frosts followed, especially in the South Island. Cold southeasterlies brought snowfall settling down to 400–500m in Canterbury and Otago from 11–13 and 20–22July.
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.