The Climate In May: Cold!

NATIONAL CLIMATE CENTRE Tuesday 2 June 2009

National Climate Summary – May 2009: Early start to winter. Lowest May temperatures ever in many locations and double normal rainfall for most of South Island

• Temperature: Well below ave/rage over most of the country; many areas experiencing lowest recorded May temperatures.
• Rainfall: Well above normal rainfall in Northland, Wairarapa, Canterbury, Otago and Southland. Above normal everywhere else with the exception of western Bay of Plenty and Tasman Districts.
• Sunshine: Below normal along Taranaki and east coast of the North Island and Central Otago; above normal in Northland, Manawatu, the south-west of the North Island, and the West Coast.

Extremely low temperatures (between 2.0 and 2.5 °C lower than normal) were recorded over most of the South Island, lower parts of the North Island, King Country, Waikato, Auckland and parts of Northland. Most other locations experienced well below average temperatures (between 1.2 and 2.0 °C lower than normal). The national average temperature of 9.0°C was 1.6°C below the long-term average for May.

Double the normal rainfall for May (about 200 percent of normal) occurred in the Wairarapa, Canterbury and Otago. Much of Northland, Auckland, Wellington and Southland received at least 150 percent of normal May rainfall. Only western Bay of Plenty (about 60 percent of normal) and Tasman District (between 20 and 60 percent of normal) received below normal rainfall for the month.

Well above normal sunshine totals for May (greater than 125 percent of normal) were recorded in Northland, Manawatu, the south-west of the North Island, and the West Coast. Below normal sunshine (between 75 and 90 percent of normal) was received along the Taranaki and eastern coasts of the North Island, and in Central Otago.

There were several extreme events during the month. Many locations received record low maximum and minimum temperatures, particularly between the 9th and the 11th and on the 21st and 22nd of May. Heavy rainfall resulted in flooding in south Canterbury on the 17th, and in Otago on the 18th. High winds buffeted Wellington on the 15th, 17th, 23rd, 24th, 30th and 31st. Snow fell to low levels periodically during the month and tornadoes damaged property in Warkworth on the 11th, and in Taranaki on the 17th.

The average pressure pattern for May 2009 was dominated by the persistence of anticyclones (“highs”) over southern Australia and more depressions (“lows”) than normal passing over and to the east of New Zealand. The average May surface pressure over New Zealand was as much as 8 hPa lower than normal. The persistent anticyclones resulted in more southerly air flows than normal over New Zealand, which led to the low temperatures experienced during the month.

Further Highlights:
• The highest temperature during May 2009 was 23.0 °C recorded at Christchurch on the 16th. The lowest temperature during May was recorded at Hanmer Forest on the 12th, where the minimum temperature was -7.0 °C.
• The highest 1-day rainfall total for May was 321 mm recorded at Mt Cook on the 16th (the highest May 1-day total for this location, since records began in 1928).
• The wind gusts of 183 km/hr recorded at Palmerston North on the 8th, and on White Island on the 20th, were the equal highest gusts for May for New Zealand.
• Of the six main centres, Tauranga was the warmest, driest and sunniest, and Wellington was the wettest.

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TEMPERATURE: LOWEST EVER FOR MAY FOR MANY AREAS, COLDER THAN NORMAL FOR ALL

The national average temperature of 9.0 °C for May 2009 was 1.6 °C below average for this time of the year. Temperatures were below average (by between 2.0 and 2.5 °C) over most of the South Island, lower parts of the North Island, King Country, Waikato, Auckland and parts of Northland. Most other locations experienced well below average temperatures (between 1.2 and 2.0 °C lower than normal). Record low May maximum or minimum temperatures were recorded in multiple locations throughout the country.

Extreme (high and low) May mean maximum daily air temperatures were recorded at:

Location / Mean maximum air temperature (°C) / Departure from normal (°C) / Year records began / Comments
Kaitaia / 15.8 / -2.5 / 1967 / Lowest
Kerikeri / 17.6 / -0.9 / 1981 / 2nd-lowest
Dargaville / 15.5 / -2.8 / 1943 / 2nd-lowest
Whangarei / 16.8 / -1.2 / 1967 / 2nd-lowest
Warkworth / 15.8 / -1.8 / 1966 / 2nd-lowest
Whangaparaoa / 15.9 / -0.9 / 1982 / 2nd-lowest
Tiri Tiri Lighthouse / 15.4 / -1.4 / 1982 / Lowest
Kumeu (Waitakere) / 15.9 / -1.7 / 1978 / Lowest
Whenuapai / 16.0 / -1.6 / 1945 / 4th-lowest
Whitianga / 16.5 / -0.9 / 1962 / 3rd-lowest
Paeroa / 15.8 / -1.5 / 1947 / 4th-lowest
Whakatane / 15.6 / -1.5 / 1974 / Lowest
Rotorua / 13.2 / -1.9 / 1964 / Lowest
Taupo / 12.4 / -1.9 / 1949 / 4th-lowest
Auckland / 15.8 / -1.4 / 1959 / 4th-lowest
Pukekohe / 15.2 / -1.6 / 1969 / 2nd-lowest
Whatawhata / 15.0 / -1.4 / 1952 / 4th-lowest
Hamilton / 14.8 / -1.9 / 1946 / 4th-lowest
Port Taharoa / 15.6 / -1.5 / 1973 / 3rd-lowest
Te Kuiti / 14.5 / -1.9 / 1959 / 2nd-lowest
Taumarunui / 13.6 / -2.0 / 1947 / 3rd-lowest
Takapau Plains / 11.9 / -2.1 / 1962 / 3rd-lowest
Dannevirke / 11.0 / -3.5 / 1951 / Lowest
Castlepoint / 12.3 / -3.2 / 1972 / Lowest
Martinborough / 12.6 / -3.2 / 1986 / Lowest
Ngawi / 12.8 / -2.8 / 1972 / Lowest
Hicks Bay / 15.2 / -1.5 / 1969 / 2nd-lowest
Hastings / 15.4 / -1.4 / 1965 / 3rd-lowest
Paraparaumu / 13.3 / -1.8 / 1953 / 3rd-lowest
Wellington / 12.9 / -2.1 / 1962 / 2nd-lowest
Stratford / 12.1 / -2.0 / 1960 / 2nd-lowest
Hawera / 13.2 / -1.6 / 1977 / 2nd-lowest
Waiouru / 8.2 / -2.9 / 1962 / 2nd-lowest
Wanganui / 13.9 / -2.0 / 1987 / 2nd-lowest
Takaka / 15.3 / -0.6 / 1978 / 4th-lowest
Farewell Spit / 14.6 / -1.5 / 1971 / 2nd-lowest
Lake Rotoiti / 10.2 / -1.3 / 1965 / 3rd-lowest
Greymouth / 13.0 / -1.4 / 1947 / 4th-lowest
Puysegur Point / 11.5 / -0.6 / 1978 / 4th-lowest
Motueka / 14.5 / -1.3 / 1956 / 4th-lowest
Pelorus Sd, Crail Bay / 13.9 / -1.5 / 1982 / 2nd-lowest
Blenheim / 13.9 / -1.9 / 1932 / 3rd-lowest
Cape Campbell / 12.3 / -2.9 / 1953 / 2nd-lowest
Kaikoura / 11.6 / -2.6 / 1963 / 3rd-lowest
Arthurs Pass / 6.7 / -3.9 / 1973 / Lowest
Cheviot / 11.4 / -3.6 / 1982 / Lowest
Mt Cook / 7.4 / -3.5 / 1929 / 2nd-lowest
Winchmore / 11.1 / -2.6 / 1928 / 2nd-lowest
Waipara West / 12.0 / -2.8 / 1973 / Lowest
Darfield / 11.0 / -3.3 / 1939 / 3rd-lowest
Christchurch / 11.2 / -3.1 / 1863 / 3rd-lowest
Lincoln / 11.6 / -2.7 / 1881 / 2nd-lowest
Le Bons Bay / 10.1 / -2.9 / 1984 / 2nd-lowest
Lake Tekapo / 7.6 / -3.2 / 1927 / 2nd-lowest
Orari / 10.9 / -2.7 / 1972 / Lowest
Timaru / 10.9 / -2.8 / 1885 / 3rd-lowest
Oamaru / 10.6 / -3.5 / 1908 / Lowest
Tara Hills / 8.4 / -3.2 / 1949 / 2nd-lowest
Wanaka / 8.9 / -3.2 / 1955 / 2nd-lowest
Dunedin / 10.5 / -2.3 / 1947 / 3rd-lowest
Manapouri / 8.7 / -3.0 / 1963 / Lowest
Queenstown / 8.7 / -2.6 / 1871 / 4th-lowest
Lumsden / 9.8 / -2.3 / 1982 / 2nd-lowest
Gore / 9.2 / -2.2 / 1971 / 2nd-lowest
Tiwai Point / 10.4 / -1.7 / 1970 / 3rd-lowest
Balclutha / 9.9 / -2.6 / 1964 / Lowest

Extreme (high and low) May mean minimum daily air temperatures were recorded at:

Location / Mean minimum air temperature (°C) / Departure from normal (°C) / Year records began / Comments
Kaitaia / 8.1 / -2.9 / 1967 / 2nd-lowest
Kerikeri / 7.7 / -1.8 / 1981 / Lowest
Warkworth / 7.2 / -3.5 / 1966 / Lowest
Whangaparaoa / 9.8 / -2.0 / 1982 / 2nd-lowest
Tiri Tiri Lighthouse / 11.0 / -0.8 / 1982 / 4th-lowest
Kumeu (Waitakere) / 6.2 / -2.0 / 1978 / 2nd-lowest
Pukekohe / 6.7 / -2.5 / 1969 / 3rd-lowest
Port Taharoa / 8.1 / -2.4 / 1973 / Lowest
Te Kuiti / 4.2 / -2.1 / 1959 / 4th-lowest
Taumarunui / 2.5 / -2.4 / 1947 / 3rd-lowest
Turangi / 2.7 / -1.6 / 1968 / 4th-lowest
Castlepoint / 8.1 / -1.9 / 1972 / 2nd-lowest
Martinborough / 4.5 / -0.9 / 1986 / 4th-lowest
Ngawi / 8.6 / -1.5 / 1972 / Lowest
Hicks Bay / 9.2 / -1.5 / 1969 / 3rd-lowest
Stratford / 4.8 / -1.5 / 1960 / 4th-lowest
Hawera / 5.8 / -1.4 / 1977 / 4th-lowest
Wanganui / 7.2 / -1.5 / 1987 / 3rd-lowest
Takaka / 2.9 / -2.8 / 1978 / 3rd-lowest
Westport / 4.9 / -2.6 / 1937 / 2nd-lowest
Hokitika / 3.8 / -2.1 / 1963 / 2nd-lowest
Greymouth / 4.7 / -2.4 / 1947 / 2nd-lowest
Motueka / 1.5 / -2.7 / 1956 / Lowest
Pelorus Sd, Crail Bay / 7.5 / -1.1 / 1982 / 2nd-lowest
Appleby / 1.7 / -3.9 / 1943 / Lowest
Blenheim / 1.6 / -2.8 / 1932 / Lowest
Kaikoura / 6.3 / -1.5 / 1963 / 4th-lowest
Arthurs Pass / -1.0 / -3.4 / 1973 / 2nd-lowest
Cheviot / 1.7 / -1.2 / 1982 / 4th-lowest
Le Bons Bay / 5.4 / -2.0 / 1984 / 2nd-lowest
Dunedin / 1.5 / -0.7 / 1947 / 2nd-lowest
Lumsden / 0.9 / -1.6 / 1982 / 4th-lowest
Tiwai Point / 3.8 / -2.0 / 1970 / 2nd-lowest
Balclutha / 1.9 / -1.9 / 1964 / 2nd-lowest

RAINFALL: VERY WET FOR MOST OF COUNTRY EXCEPT TASMAN AND WESTERN BAY OF PLENTY

Double the normal rainfall for May (about 200 percent of normal) occurred in the Wairarapa, Canterbury and Otago. Much of Northland, Auckland, Wellington and Southland received at least 150 percent of normal May rainfall. The following locations received record high May rainfall: Kumeu (Waitakere), Lake Tekapo, Timaru, and Tara Hills. The western Bay of Plenty (about 60 percent of normal) and Tasman District (between 20 and 60 percent of normal) received below normal rainfall for the month.

Extreme (high and low) May rainfall totals were recorded at:

Location / Rainfall total (mm) / Percentage of normal / Year records began / Comments
Dargaville / 219 / 209 / 1943 / 4th-highest
Warkworth / 205 / 177 / 1966 / 3rd-highest
Kumeu (Waitakere) / 179 / 174 / 1978 / Highest
Martinborough / 177 / 241 / 1924 / 3rd-highest
Hawera / 162 / 175 / 1977 / 4th-highest
Mt Cook / 809 / 220 / 1928 / 3rd-highest
Lake Tekapo / 186 / 373 / 1925 / Highest
Tara Hills / 116 / 243 / 1949 / Highest
Ranfurly / 65 / 203 / 1943 / 4th-highest
Dunedin / 168 / 241 / 1918 / 4th-highest
Manapouri / 186 / 177 / 1961 / 3rd-highest
Lumsden / 100 / 108 / 1982 / 3rd-highest
Balclutha / 113 / 195 / 1964 / 3rd-highest
Takaka / 65 / 39 / 1976 / 4th-lowest
Nelson / 21 / 28 / 1941 / 4th-lowest
Appleby / 24 / 31 / 1941 / 4th-lowest

SUNSHINE: ABOVE NORMAL FOR NORTHLAND, MANAWATU, HOROWHENUA-KAPITI, WELLINGTON AND WEST COAST; BELOW NORMAL FOR WEST AND EAST COAST OF NORTH ISLAND AND CENTRAL OTAGO

Well above normal sunshine totals for May (greater than 125 percent of normal) were recorded in Northland (with Kaitaia receiving record high sunshine), Manawatu, Kapiti, and the West Coast. Below normal sunshine (between 75 and 90 percent of normal) was received along the Taranaki and eastern coasts of the North Island, and in Central Otago. Record low sunshine for May was recorded in Martinborough and Stratford.

Extreme (high and low) May sunshine hours were recorded at:

Location / Sunshine (hours) / Percentage of normal / Year records began / Comments
Kaitaia / 185 / 124 / 1985 / Highest
Greymouth / 165 / 166 / 1947 / Highest
Cheviot / 144 / 118 / 1983 / 3rd-highest
Turangi 2 Ews / 123 / 84 / 1976 / 4th-lowest
New Plymouth Aero / 119 / 83 / 1972 / 4th-lowest
Martinborough Ews / 92 / 69 / 1986 / Lowest
Stratford Ews / 98 / 79 / 1963 / Lowest

MAY CLIMATE IN THE SIX MAIN CENTRES

Temperatures for May were below average for Tauranga (the warmest of the main centres) and well below average for the other main centres (with Hamilton, Christchurch and Dunedin recording near-record low temperatures). Rainfall was well above normal in Wellington (the wettest of the main centres), Christchurch and Dunedin, above normal in Auckland, and near normal in Hamilton and Tauranga (the driest of the main centres). Sunshine totals were near normal everywhere except in Auckland and Hamilton, which had above normal sunshine. Tauranga received the most sunshine hours for the month.

May 2009 main centre climate statistics: /

Location / Mean temp. (°C) / Departure from normal (°C) / / Rainfall (mm) / % of normal / / Sunshine (hours) / % of normal /
Aucklanda / 11.8 / -2.0 / Well below average / 142 / 139 / Above normal / 153 / 110 / Above normal
Taurangab / 12.0 / -0.8 / Below average / 72 / 81 / Near normal / 169 / 105 / Near normal
Hamilton / 9.9 / -1.4 / 3rd lowest since 1946 / 91 / 86 / Near normal / 144d / 110 / Above normal
Wellington / 9.7 / -1.8 / Well below average / 185 / 159 / Well above normal / 130 / 101 / Near normal
Christchurchc / 6.9 / -2.0 / 3rd lowest since 1863 / 145 / 277 / Well above normal / 134 / 95 / Near normal
Dunedin / 7.4 / -1.9 / 4th lowest since 1947 / 168 / 241 / 4th highest since 1918 / 100 / 101 / Near normal
a Mangere b Tauranga Airport c Christchurch Airport d Ruakura

HIGHLIGHTS AND EXTREME EVENTS

• Temperature
The highest temperature during May 2009 was 23.0 °C recorded at Christchurch on the 16th (not a May maximum temperature record for this location). There were only two locations in New Zealand that recorded near-record high minimum temperatures during the entire month, Kaikoura and Fairlie on the 17th, and no locations at all that had near-record high maximum temperatures.

Record or near record high extreme daily minimum air temperatures were recorded at:

Location / Extreme minimum temperature (ºC) / Date of extreme temperature / Year Records began / Comments
Kaikoura / 14.8 / 17th / 1972 / 4th-highest
Fairlie / 8.0 / 17th / 1972 / Equal 4th-highest

The lowest temperature during May was recorded at Hanmer Forest on the 12th, where the minimum temperature was -7.0 °C (not a record for this location). There were several locations that recorded record-low minimum and maximum temperatures for May (see tables below).
Record or near record low extreme daily minimum air temperatures were recorded at:

Location / Extreme minimum temperature (ºC) / Date of extreme temperature / Year Records began / Comments
Kaitaia Observatory / 4.7 / 24th / 1985 / Equal 3rd-lowest
Kerikeri Ews / 3.0 / 22nd / 1981 / Equal 3rd-lowest
Warkworth Ews / 0.1 / 22nd / 1966 / Lowest
Whangaparaoa Aws / 5.4 / 21st / 1982 / Lowest
Te Puke Ews / -1.0 / 22nd / 1973 / Equal 2nd-lowest
Whakatane Aero Aws / -1.6 / 22nd / 1975 / 2nd-lowest
Rotorua Aero Aws / -2.9 / 22nd / 1964 / Lowest
Taupo Aws / -4.1 / 22nd / 1949 / 3rd-lowest
Pukekohe Ews / -0.5 / 22nd / 1969 / 3rd-lowest
Port Taharoa Aws / 2.0 / 21st / 1973 / Lowest
Te Kuiti Ews / -2.5 / 22nd / 1959 / 3rd-lowest
Taumarunui Aws / -4.0 / 22nd / 1947 / 3rd-lowest
New Plymouth Aws / -0.8 / 22nd / 1944 / Lowest
Ngawi Aws / 4.6 / 28th / 1972 / 4th-lowest
Hicks Bay Aws / 1.7 / 22nd / 1969 / 3rd-lowest
Hastings Aws / -2.4 / 22nd / 1965 / 2nd-lowest
Waipawa Ews / -4.2 / 22nd / 1945 / 2nd-lowest
Wairoa, North Clyde Ews / -0.2 / 22nd / 1964 / 4th-lowest
Stratford Ews / -1.8 / 22nd / 1960 / Equal 2nd-lowest
Waiouru Aws / -6.1 / 22nd / 1962 / 4th-lowest
Wanganui Aws / 1.3 / 28th / 1987 / Equal 4th-lowest
Hokitika Aero / -1.8 / 12th / 1963 / 2nd-lowest
Pelorus Sd, Crail Bay / 2.0 / 21st / 1982 / 3rd-lowest
Blenheim Aero Aws / -4.7 / 21st / 1932 / Lowest
Le Bons Bay Aws / 0.8 / 21st / 1984 / 3rd-lowest
Dunedin Aero Aws / -4.9 / 3rd / 1947 / 3rd-lowest
Balclutha, Telford Ews / -4.5 / 2nd / 1964 / Equal 3rd-lowest

Record or near record low extreme daily maximum air temperatures were recorded at:

Location / Extreme maximum temperature (ºC) / Date of extreme temperature / Year Records began / Comments
Kaitaia / 12.7 / 11th / 1972 / Equal lowest
Kerikeri / 12.0 / 11th / 1981 / Lowest
Kaikohe / 11.8 / 11th / 1973 / 4th-lowest
Dargaville / 11.4 / 2nd / 1951 / Lowest
Whangarei / 11.8 / 2nd / 1967 / Lowest
Warkworth / 11.5 / 21st / 1966 / 2nd-lowest
Whangaparaoa / 11.9 / 21st / 1982 / Lowest
Kumeu (Waitakere) / 11.2 / 2nd / 1978 / Lowest
Whenuapai / 12.0 / 2nd / 1951 / Equal 3rd-lowest
Whitianga / 12.2 / 21st / 1972 / 4th-lowest
Paeroa / 11.0 / 22nd / 1972 / 3rd-lowest
Rotorua / 9.5 / 22nd / 1972 / 4th-lowest
Pukekohe / 11.2 / 11th / 1972 / 4th-lowest
Whatawhata / 8.8 / 22nd / 1952 / Equal 2nd-lowest
Ruakura / 8.0 / 22nd / 1940 / Lowest
Hamilton / 7.0 / 22nd / 1946 / Lowest
Port Taharoa / 11.3 / 11th / 1974 / 3rd-lowest
Te Kuiti / 8.4 / 22nd / 1959 / Lowest
Taumarunui / 8.3 / 22nd / 1947 / 4th-lowest
Takapau Plains / 5.1 / 31st / 1972 / 2nd-lowest
Dannevirke / 5.0 / 31st / 1951 / Lowest
Castlepoint / 7.7 / 31st / 1972 / Lowest
Martinborough / 7.4 / 21st / 1986 / Lowest
Ngawi / 9.3 / 20th / 1972 / Lowest
Hicks Bay / 11.0 / 31st / 1972 / 2nd-lowest
Napier / 8.7 / 31st / 1940 / Equal 3rd-lowest
Waipawa / 7.5 / 31st / 1945 / 2nd-lowest
Wairoa / 10.0 / 31st / 1972 / Equal 3rd-lowest
Paraparaumu / 8.3 / 31st / 1972 / 3rd-lowest
Levin / 8.9 / 31st / 1950 / 4th-lowest
Wellington / 9.7 / 31st / 1972 / 4th-lowest
Wallaceville / 7.3 / 31st / 1972 / 2nd-lowest
Stratford / 5.4 / 31st / 1972 / Equal lowest
Hawera / 8.5 / 20th / 1977 / 3rd-lowest
Waiouru / 1.5 / 31st / 1972 / Equal lowest
Wanganui / 8.5 / 31st / 1972 / Lowest
Takaka / 11.0 / 10th / 1978 / 4th-lowest
Farewell Spit / 11.3 / 10th / 1972 / 3rd-lowest
Haast / 6.3 / 9th / 1949 / Lowest
Blenheim / 8.5 / 31st / 1972 / Equal 3rd-lowest
Hanmer Forest / 1.8 / 31st / 1972 / 2nd-lowest
Kaikoura / 6.3 / 10th / 1972 / 3rd-lowest
Arthurs Pass / 0.2 / 31st / 1973 / 2nd-lowest
Cheviot / 4.9 / 10th / 1982 / Lowest
Winchmore / 4.8 / 10th / 1928 / 2nd-lowest
Waipara West / 5.5 / 10th / 1973 / 2nd-lowest
Darfield / 4.2 / 10th / 1954 / 2nd-lowest
Christchurch / 5.4 / 20th / 1863 / Equal 3rd-lowest
Lincoln / 6.0 / 20th / 1881 / 4th-lowest
Le Bons Bay / 5.6 / 10th / 1984 / 2nd-lowest
Woodbury / 5.0 / 28th / 1973 / 2nd-lowest
Orari / 4.4 / 28th / 1972 / Lowest

• Heavy rain and flooding
The highest 1-day rainfall total for May was 321 mm recorded at Mt Cook on the 16th (the highest May 1-day total for this location, since records began in 1928). Record high 1-day rainfalls for May were also recorded at Lake Tekapo, Woodbury, Timaru, and Tara Hills.

Record or near record high extreme 1-day rainfall totals were recorded at:

Location / Extreme 1-day rainfall (mm) / Date of extreme rainfall / Year Records Began / Comments
Kerikeri / 102 / 26th / 1981 / 2nd-highest
Arthurs Pass / 214 / 16th / 1906 / 2nd-highest
Mt Cook / 321 / 16th / 1928 / Highest
Lake Tekapo / 88 / 16th / 1925 / Highest
Woodbury / 150 / 5th / 1973 / Highest
Tara Hills / 70 / 16th / 1949 / Highest
Manapouri / 37 / 14th / 1963 / 3rd-highest

On 14 May, rain in Southland closed SH99 between Riverton and Invercargill, and SH6 was reduced to one lane at Makarewa Bridge. Several other minor roads were also closed. Access to Toko Mouth in Southland was restored on 14 May after flooding closed the road for three days.

On 17 May, SH1 south of Ashburton, was closed for several hours after the Rangitata River burst its banks. The main railway line between Rangitata River and Temuka was also closed by flooding, delaying three freight trains. Inland, Omarama had water up to 1 m deep in places, after a stopbank designed to cope with a 100-year flood was overtopped. About 30 people were evacuated from the camping ground, along with three residents living near the river. A major slip closed SH8, on the Omarama side of the Lindis Pass.

On 18 May, farmers used boats to rescue 150 sheep, stranded by the flooded Clutha River at Barnego, near Balclutha. The Skippers Road in Queenstown was closed until further notice, after slips and washouts at various locations. The previous three days of rain had also damaged many roads in the Queenstown Lakes area, with access requiring four-wheel drive vehicles.

On the morning of 20 May, a 12 m stretch of Whitewash Head Road above Scarborough in Christchurch gave way following heavy rainfall. Vehicle access was affected to 23 homes.

On 24 May, residents were evacuated from two houses after a slip in Sumner, Christchurch. In Otago, a slip on Portobello Rd disrupted traffic for about an hour and a-half. And further north, a slip on the Rimutaka Hill Road partly blocked both lanes, but was eventually cleared.

• High winds and tornadoes
The wind gusts of 183 km/hr recorded at Palmerston North on the 8th and on White Island on the 20th were the equal highest gusts for May for New Zealand, though they were not May records for either location.

Record or near record high extreme wind gusts were recorded at:

Location / Extreme wind gust speed (km/hr) / Date of extreme gust / Year Records began / Comments
Cape Reinga / 150 / 8th / 1974 / 3rd-highest
Kaikohe / 83 / 8th / 1986 / Equal highest
Hawera / 82 / 24th / 1986 / 4th-highest
Milford Sound / 120 / 10th / 1974 / 4th-highest
Blenheim / 93 / 17th / 1972 / 2nd-highest

Strong winds buffetted Wellington on 15 May, damaging power lines and cutting power for a few hours to 2500 homes in Karori and Makara. Four domestic flights into the capital were cancelled and another four were diverted to other airports. Two flights out of the city were cancelled. Trees and fences were blown down, and a parked van was lifted up on to the footpath on Evans Bay Parade. A large glass roof panel on Miramar Library, and a glass veranda panel from an apartment above Taranaki St were damaged.

On 17 May, high winds blew a tree down across SH2 at White Pines Bush, about 15 km north of Napier. In Wellington, flying debris from gales knocked out power for 2-3 hours to about 3000 homes Upper Hutt, Lower Hutt, and Johnsonville. SH77 was closed to campervans and other high-sided vehicles because of the high winds.

On 20 May, wind gusts brought down a tree, blocking SH75 near Akaroa. Further north, the gales caused the delay or cancellation of Cook Strait ferries.

Southerly gales hammered Wellington over the weekend of 23-24 May, closing roads, tearing boats from their moorings, and damaging trees, roofs and power lines. Cook Strait ferries were cancelled, and flights were delayed, cancelled or diverted. Trees brought down power poles near Upper Hutt cutting power to about 1200 houses on 23 May. Power was restored to most homes after several hours, but a few customers were without power until the evening of the 24th. A fallen tree blocked SH2 at Tutira, 45 km from Napier, closing the road for at least two hours.

Eastern South Island, Wellington and eastern North Island were buffeted by high winds over the weekend of 30-31 May. Two teenage girls were rescued in atrocious weather and strong southerly winds kayaking off New Plymouth's East End Beach on 31 May.

• Snow
Snow fell on Milford Rd in Fiordland on 5 May, causing minor traffic disruptions.

Snow fell in Central Otago and the Southern Lakes area on 8 May, with 10 cm at Coronet Peak and 15 cm at the Remarkables ski field.

A cold front brought 10-20 cm of snow to inland Otago on 10 May. More than 80 people were trapped for several hours in three tour buses on the Lindis Pass, when it was closed overnight by snow and ice. SH87 from Outram to Middlemarch was also closed.. Both roads were re-opened on 11 May. Mt Hutt staff reported a base of 110 cm. after about 170 cm of snow was recorded in 10 days. In the North Island, Mount Taranaki had a snow base of up to 50 cm by 12 May, enough to consider opening the lower and learner's slopes and t-bar.

By 18 May, The Remarkables, Treble Cone, Cardrona, and Snow Park skifields had received between 50 cm and 1 m of snow over the preceding three days.

Snow closed the Desert Road in the early hours of 20 May, and in Dunedin, Three Mile Hill Road was closed indefinitely and the Northern Motorway open to light vehicles only. SH87 between Outram and Middlemarch, SH85 between Palmerston and Kyeburn, and the Lindis Pass were also closed by snow.

On 21 May, SH4 between National Park and Raetihi, and the Desert Road were closed by snow and ice for a few hours. Some schools on the Central Plateau were closed for the day. Between 30 cm and 40 cm of snow fell on the upper slopes of Whakapapa ski field. In Taranaki, snow was reported in Stratford, and black ice caused many motor vehicle accidents. Manganui Ski Field was open with 12 cm of new snow.

Snow, slips and a fallen tree closed the highway between Opotiki and Gisborne on 31 May as wintry conditions brought snow and ice to the country's roads. SH2, the Waioeka Gorge Road, was closed and SH7, Lewis Pass, was closed to towing vehicles. Snow fell to sea level along Wellington's south coast and from Southland to Kaikoura, and blanketed high-country passes, including the Rimutaka Hill Road summit and Desert Road. Snow fell at Mt Hutt skifield adding another 15 cm to the more than 2 m of snow that had fallen in May, and snow settled to about 200 m inland and elsewhere around Canterbury, with about 8 cm on the ground near Springfield and in parts of Otago.

• Hail
On 11 May, thunderstorms and hail struck Tauranga, Whakatane and Opotiki with hail stones the size of a 20 cent coin, up to 10 cm deep in places, blocking drains and flooding several streets and houses. The hail cut a ragged swathe across kiwifruit orchards, devastating some orchards and bypassing others completely. At Papamoa School a ceiling collapsed and classrooms were flooded.

• Lightning
Wellington was hit by thunder, lightning and hail in the early morning of 6 May. Minor flooding affected the southern suburbs, and hail up to 5 cm deep was reported in the eastern suburbs.

Thunderstorms and hail affected Hamilton mid afternoon on 10 May.

Taranaki was affected by lightning strikes on 17 May, damaging transformers and downing powerlines, cutting power to 230 properties.

• Waterspouts
On 20 May, several large waterspouts were reported offshore from Papamoa between Motiti Island and Town Point, accompanied by very strong winds.

• Tornado
A tornado damaged homes in Warkworth on 11 May.

Taranaki was hit by a mini tornado on 17 May, with a trampoline flung 40 m, windows smashed, and about 20 trees flattened on a property in Opunake. Nearby 15 30-year old trees were knocked over, and three sides of a hay barn were flung 100 m across a paddock, leaving the hay stacked nicely.

ENDS

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