Wednesday 2 January 2002
In the North Island very wet with warm nights Record low sunshine hours in many regions Dry in Canterbury
New rainfall records were set in many areas during a warm but unsettled December. Many northern and eastern North Island areas received at least twice their average December rainfall, with some locations establishing new records. Records were set at Kerikeri, Motu, Mahia, Turangi, Whakatu near Hastings, Masterton and Lake Rotoiti in the Nelson Lakes district. It was also wetter than usual in many other regions, with rain falling on more than 20 days in many North Island locations. Record low monthly sunshine hours occurred in many regions. In contrast, low rainfall occurred in Canterbury, with totals only half average. Soil moisture deficits are high in parts of Canterbury and Central Otago, but not severe as at the end of December 2000.
It was extremely warm throughout much of the North Island, due to well above average night-time temperatures. These were the highest on record throughout most of the North Island, and some South Island locations, with values between 2 and 3°C above average. Mean temperatures were near average in Central Otago. The national average temperature of 16.6°C was 0.9°C above the mean December temperature during 1961–1990.
The overall December climate pattern involved many more depressions (‘lows’) than usual in the eastern Tasman Sea and over New Zealand, producing more frequent and moist northerlies over the North Island and easterlies over the South Island with persistent cloud cover.
Extremely low sunshine hours in many regions
Sunshine and solar radiation totals were less than 70 percent of average in many northern and western regions, and less than 90 percent of average elsewhere. Near or record low December sunshine hours were recorded at:
Location |
December sunshine (hours) |
Percentage of normal |
Year records began |
Comments |
---|---|---|---|---|
Kaitaia Observatory |
163* |
75 |
1985 |
Equal lowest |
Whakatane |
135 |
59 |
1957 |
Lowest |
Taumarunui |
111 |
58 |
1947 |
Lowest |
New Plymouth Airport |
165 |
71 |
1972 |
Lowest |
Paraparaumu Airport |
135 |
60 |
1953 |
Lowest |
Wellington, Kelburn |
153 |
62 |
1928 |
2nd lowest |
Hokitika Airport |
123 |
63 |
1964 |
Lowest |
Nelson Airport |
164 |
68 |
1948 |
Lowest |
Extremely wet in the North Island, dry in Canterbury
Rainfall was at least double normal throughout much of the North Island, and more than 300 percent (3 times) of normal in parts of north Taranaki and eastern Bay of Plenty. It was also wet with at least 120 percent of normal rainfall in Nelson, Buller, Westland, the Southern Alps, and Central Otago. Contrasting below average rainfall occurred in parts of Canterbury and Southland where totals were 75 percent or less than average.
Near or record high December rainfall was recorded at:
Location |
December rainfall (mm) |
Percentage of normal |
Year records began |
Comments |
---|---|---|---|---|
Cape Reinga |
172 |
280 |
1919 |
2nd highest |
Kaitaia Observatory |
180 |
215 |
1985 |
2nd highest |
Kerikeri |
235 |
241 |
1935 |
Highest |
Kerikeri Airport |
270 |
247 |
1978 |
Highest |
Great Barrier Island |
182 |
226 |
1977 |
3rd highest |
Manukau Heads |
174 |
207 |
1935 |
2nd highest |
Whitianga Airport |
296 |
282 |
1987 |
2nd highest |
Whakatane |
239 |
286 |
1992 |
Very high |
Motu |
449 |
261 |
1990 |
Highest |
Port Taharoa |
225 |
238 |
1973 |
2nd highest |
New Plymouth Airport |
346 |
318 |
1944 |
2nd highest |
Taumarunui |
308 |
225 |
1913 |
2nd highest |
Turangi |
314 |
246 |
1968 |
Highest |
Castlepoint |
165 |
258 |
1902 |
3rd highest |
East Taratahi |
137 |
253 |
1972 |
Highest |
Hicks Bay |
305 |
340 |
1990 |
2nd highest |
Napier Airport |
188 |
254 |
1950 |
2nd highest |
Napier, Nelson Park |
172 |
259 |
1870 |
2nd highest |
Whakatu |
143 |
467 |
1982 |
Highest |
Mahia |
165 |
255 |
1990 |
Highest |
Wanganui |
173 |
224 |
1890 |
2nd highest |
Wellington Airport |
134 |
181 |
1960 |
2nd highest |
Lake Rotoiti |
324 |
220 |
1933 |
Highest |
Reefton |
335 |
197 |
1904 |
2nd highest |
Unusually warm nights in the North Island
Mean temperatures were at least 1.0°C above normal throughout much of the North Island, as well as Buller, Westland, Fiordland, Marlborough and Nelson, due to persistent cloud and moist northerlies keeping overnight temperatures well above average. Mean temperatures were at 0.5 to 0.9°C above average in most other regions, but near average in Central Otago.
Near or record high mean December temperatures were recorded at:
Location |
Mean temperature |
Departure (°C) |
Records began |
Comments |
---|---|---|---|---|
Kaitaia Observatory |
19.0 |
+1.2 |
1985 |
2nd highest |
Warkworth |
18.5 |
+1.6 |
1972 |
Highest |
Tauranga Airport |
19.0 |
+1.6 |
1913 |
3rd highest |
Whakatane Airport |
19.0 |
+2.0 |
1974 |
Highest |
Auckland Airport |
19.4 |
+1.4 |
1962 |
Equal highest |
Pukekohe |
18.6 |
+1.7 |
1970 |
2nd highest |
Hamilton Airport |
18.5 |
+2.0 |
1970 |
Highest |
New Plymouth Airport |
17.7 |
+1.6 |
1944 |
Equal highest |
Napier Airport |
19.1 |
+1.6 |
1973 |
2nd highest |
Palmerston North Airport |
17.7 |
+1.7 |
1962 |
3rd equal highest |
Levin |
17.8 |
+1.8 |
1895 |
2nd equal highest |
Normanby |
17.1 |
+1.8 |
1977 |
Highest |
Wanganui |
18.4 |
+1.6 |
1937 |
3rd highest |
Westport |
16.5 |
+1.5 |
1937 |
2nd equal highest |
Raoul Island |
22.7 |
+2.1 |
1940 |
Highest |
Chatham Islands |
16.2 |
+2.5 |
1956 |
Highest |
Near or record high mean daily minimum December temperatures were recorded at:
Location |
Mean daily minimum temperature |
Departure from normal (°C) |
Year records began |
Comments |
---|---|---|---|---|
Kaitaia Observatory |
15.7 |
+2.2 |
1985 |
Highest |
Kerikeri |
15.0 |
+2.1 |
1945 |
Highest |
Whangarei Airport |
16.0 |
+2.2 |
1967 |
Highest |
Auckland, Henderson |
15.3 |
+2.7 |
1985 |
Highest |
Auckland, Owairaka |
16.1 |
+2.3 |
1949 |
Highest |
Auckland Airport |
16.5 |
+2.1 |
1962 |
Highest |
Pukekohe |
15.4 |
+2.8 |
1970 |
Highest |
Paeroa |
15.1 |
+2.7 |
1947 |
2nd highest |
Tauranga Airport |
15.7 |
+2.7 |
1913 |
Highest |
Hamilton, Ruakura |
14.6 |
+3.2 |
1906 |
Highest |
Hamilton Airport |
14.7 |
+4.1 |
1970 |
Highest |
Whakatane Airport |
15.5 |
+3.3 |
1974 |
Highest |
Rotorua Airport |
14.3 |
+3.0 |
1964 |
Highest |
Taupo Airport |
12.9 |
+2.6 |
1976 |
Highest |
Taumarunui |
13.9 |
+2.8 |
1947 |
Highest |
New Plymouth Airport |
15.0 |
+2.9 |
1944 |
Highest |
East Taratahi |
12.2 |
+2.8 |
1972 |
Highest |
Gisborne Airport |
15.2 |
+3.1 |
1905 |
Highest |
Napier Airport |
15.0 |
+2.4 |
1973 |
Equal highest |
Napier, Nelson Park |
15.8 |
+2.6 |
1870 |
3rd highest |
Whakatu |
14.1 |
+1.9 |
1982 |
Highest |
Paraparaumu Airport |
14.6 |
+2.5 |
1953 |
Highest |
Palmerston North Airport |
13.9 |
+2.7 |
1962 |
Highest |
Levin |
14.4 |
+2.4 |
1895 |
Highest |
Wellington Airport |
14.8 |
+1.6 |
1962 |
2nd highest |
Normanby |
13.9 |
+2.8 |
1977 |
Highest |
Wanganui |
15.0 |
+2.2 |
1937 |
Highest |
Westport Airport |
13.5 |
+2.2 |
1937 |
2nd highest |
Hokitika Airport |
12.6 |
+2.1 |
1963 |
3rd highest |
Nelson Airport |
14.1 |
+2.4 |
1943 |
Highest |
Tara Hills |
9.6 |
+2.0 |
1949 |
Highest |
Dunedin Airport |
10.4 |
+2.1 |
1962 |
2nd highest |
Raoul Island |
19.8 |
+1.7 |
1940 |
3rd highest |
Chatham Islands |
13.8 |
+2.9 |
1956 |
Highest |
Highlights
Extreme temperatures
- The highest air temperature for the month was 32.0°C, recorded at Darfield, on the 1st. The highest December air temperature on record in the Darfield area is 35.8°C. Wanganui experienced an extended heat-wave at the start of the month, with maximum temperatures exceeding 25.0°C on five days from 1 through 6 December.
- The lowest air temperature for the month was –0.9°C, recorded at Wreys Bush, Southland on the 9th. The lowest December air temperature on record in the Wreys Bush area is –1.0°C.
Significant rainfall events and flooding
- High rainfall occurred throughout Northland on the 2nd. The Awanui River peaked 7 metres above normal blocking off parts of SH 12 due to flooding.
Hail
- Hail lay 4 cm deep in parts of Rangiora following a convectional storm during the afternoon of the 28th.
Snow
- Mt Ruapehu received an unseasonal dusting of snow on the 30th.
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.