This month’s cold snap has broken a swathe of temperature records around the country.
NIWA data shows at more than 30 weather stations from Cape Reinga in the north to Stewart Island, had daily maximum temperature recordings that were either the lowest ever recorded, or at least in the top four coldest for July.
At South West Cape, the southernmost point on Stewart Island the temperature reached just 5.2°C on July 6. This was the third lowest for July for this location since records began in 1991.
At the opposite end of the country at Cape Reinga the temperature was a comparably balmy 10.8°C on July 10, but this was the lowest daily maximum July temperature there since 1971.
Lowest daily maximum temperatures were also recorded at Kaitaia, Port Taharoa, Waione and Ngawi.
Suspicions that the early mornings for the first half of July have been especially chilly have also been confirmed at several locations.
In particular Northlanders have been feeling the cold with Kaitaia, Kerikeri and Warkworth all recording the lowest July temperature on record. Kaitaia’s lowest daily minimum was 0°C on July 11, Kerikeri’s -0.7°C on July 12 and Warkworth’s -2.3°C also on July 12.
Te Kuiti plummeted to -4.9°C overnight on July 13, marking it as the coldest July temperature for the town since records began in 1959. In fact, Te Kuiti has observed its two-lowest July temperatures on record over the past three days: -4.5°C was recorded on July 11 which is its second-lowest July temperature.
And in Greymouth -2.6°C on July 9 put it in the record books as the coldest July temperature there since records begin in 1947.
NIWA climate scientist Gregor Macara said the cold weather was caused by a cold southerly flow that brought icy showers and snow last week, followed by a high pressure system bringing clear skies and little wind to most of the country.
“Clouds act like a blanket at night and trap heat over the Earth’s surface, whereas clear skies enable enhanced night-time cooling as this heat escapes the atmosphere. This process has contributed to the severe frosts observed lately,” he said.
The current list of July 2015 record breakers is:
Lowest Daily Maximum Temperature Extremes |
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LOCATION |
Daily Tmax (°C) |
Date |
Year records began |
Ranking |
Cape Reinga |
10.8 |
10th |
1971 |
Lowest |
Kaitaia |
9.6 |
10th |
1971 |
Lowest |
Dargaville |
9.4 |
9th |
1951 |
2nd-lowest |
Mokohinau |
10.0 |
10th |
1994 |
Equal lowest |
Warkworth |
9.8 |
9th |
1966 |
4th-lowest |
Whangaparaoa |
9.9 |
10th |
1982 |
Equal 2nd-lowest |
Whitianga |
9.8 |
9th |
1971 |
2nd-lowest |
Paeroa |
8.8 |
9th |
1971 |
4th-lowest |
Te Puke |
8.6 |
8th |
1973 |
4th-lowest |
Whakatane |
9.3 |
8th |
1975 |
Equal 4th-lowest |
Rotorua |
7.1 |
8th |
1972 |
Equal 3rd-lowest |
Motu |
3.8 |
8th |
1990 |
3rd-lowest |
Port Taharoa |
9.0 |
8th |
1974 |
Lowest |
Te Kuiti |
6.3 |
9th |
1959 |
2nd-lowest |
Turangi |
5.7 |
9th |
1968 |
4th-lowest |
Takapau Plains |
3.8 |
9th |
1972 |
2nd-lowest |
Dannevirke |
4.0 |
9th |
1951 |
2nd-lowest |
Waione |
4.9 |
9th |
1993 |
Lowest |
Castlepoint |
6.5 |
8th |
1972 |
3rd-lowest |
Ngawi |
6.9 |
8th |
1972 |
Lowest |
Hicks Bay |
8.1 |
8th |
1972 |
Equal lowest |
Gisborne |
6.9 |
9th |
1940 |
3rd-lowest |
Napier |
7.5 |
9th |
1940 |
4th-lowest |
Hastings |
6.6 |
9th |
1972 |
2nd-lowest |
Wairoa |
7.6 |
8th |
1972 |
2nd-lowest |
Mahia |
7.4 |
9th |
1990 |
Equal 2nd-lowest |
Ohakune |
2.2 |
9th |
1972 |
Equal 3rd-lowest |
Haast |
6.1 |
6th |
1949 |
4th-lowest |
Secretary Island |
5.9 |
6th |
1989 |
3rd-lowest |
Le Bons Bay |
3.4 |
8th |
1984 |
2nd-lowest |
South West Cape |
5.2 |
6th |
1991 |
3rd-lowest |
Lowest Daily Minimum Temperature Extremes |
||||
LOCATION |
Daily Tmin (°C) |
Date |
Year records began |
Ranking |
Kaitaia |
0.0 |
11th |
1948 |
Lowest |
Kerikeri |
-0.7 |
12th |
1981 |
Lowest |
Warkworth |
-2.3 |
12th |
1966 |
Lowest |
North Shore, Auckland |
1.0 |
12th |
1994 |
Equal 3rd-lowest |
Port Taharoa |
0.9 |
10th |
1973 |
Equal 2nd-lowest |
Te Kuiti |
-4.9 |
13th |
1959 |
Lowest |
Taumarunui |
-5.9 |
12th |
1947 |
Equal 4th-lowest |
Mahia |
1.8 |
9th |
1990 |
2nd-lowest |
Westport |
-1.3 |
9th |
1937 |
4th-lowest |
Greymouth |
-2.6 |
9th |
1947 |
Lowest |
Puysegur Point |
1.1 |
7th |
1978 |
4th-lowest |
Appleby |
-5.6 |
11th |
1932 |
4th-lowest |
Waiau School |
-7.3 |
12th |
1974 |
Equal 4th-lowest |
Dunedin (Musselburgh) |
-3.1 |
13th |
1947 |
Equal 2nd-lowest |
Alexandra |
-8.7 |
12th |
1983 |
4th-lowest |
Balclutha |
-6.1 |
13th |
1964 |
2nd-lowest |