Climate Summary for February 2008

February 2008: A Northland flood, but generally a very dry North Island

• Rainfall: Very wet in Northland, and north and central Canterbury; dry over the remainder of the North Island
• Soil moisture:  Significant deficits in many North Island areas, Marlborough, and the southeast of the South Island
• Temperature: Above average in western areas, especially South Island southwest
• Sunshine: Extremely high in the south, and also the southwest of the North Island.

February was a month of contrasts.

Rainfall was 50% (half) or less of normal over much of the North Island from Manukau southwards, and in coastal Otago and parts of Southland. As a result, severe soil moisture deficits (more than 130 mm) persisted in Waikato, parts of Bay of Plenty, South Taranaki and northern Manawatu, Hawke’s Bay, Wairarapa, as well as Marlborough, and parts of south Canterbury, Otago and Southland.

In contrast, rainfall was at least twice (double) normal in Northland, and north and central Canterbury. A low east of Canterbury produced 30 – 70 mm in Canterbury. Wet northeasterlies on the 23^rd and 24^th produced 200 – 237 mm in the hills between Kaeo and Kaikohe with some flooding near Kaeo. The same system brought gale northeasterly winds to Northland and Auckland.

February temperatures were above average in western areas, especially in Fiordland, whilst these were near average on the north of the South Island, and the northeast of the North Island. The national average temperature of 17.7°C was 0.5°C above average.

Once again Otago and Southland basked in very sunny conditions.

The month’s overall climate pattern was produced by many more lows from the sub tropics and west of New Zealand producing light more north easterlies over the country.

Further Highlights

• The lowest air temperature during the month was -1.1 ºC recorded at Hanmer Forest on the 6^th. The highest temperature during February 2008 was 33.6 ºC recorded at Christchurch Airport on the 1^st.
• A low crossed the South Island on 11/12^th triggering thunderstorms with heavy rain, hail and flash flooding in the Canterbury foothills and north Canterbury. These same thunderstorms produced 64 mm at Amberley and 77 mm at Rangiora. A deluge of 23 mm in one hour occurred in Lower Hutt.
• Another subtropical low brought between 200 and 240 mm to the hills between Kaeo and Kaikohe on 22 and 23^rd, with wind gusts as high as 145 km/h at Cape Reinga, the highest wind gust for the month. This produced some flooding to Kaeo and blacked out the power to 500 homes north of Wellsford.
• Of the five main centres, Auckland was the warmest, Hamilton the driest, Christchurch the wettest and Wellington the sunniest.

Rainfall

February 2008 rainfall was less than 50 percent (half) of normal in many central and southern areas of the North Island, central Marlborough, coastal Otago and Southland, and only 25 percent (a quarter) of normal in coastal Wairarapa. In contrast totals of 200 percent (double) or more of normal occurred in eastern Northland, and north and central Canterbury.

Temperature

Mean temperatures were at least 0.5 ºC above average in the southwest of the South Island, and 0.5°C above average in other western areas of New Zealand.

Sunshine

Sunshine hours were 115 percent of normal from Taranaki to Kapiti, and in Southland and Otago. Sunshine totals were close to, or slightly above average in other areas.

Full report

• Full details of the February 2008 Climate Summary

For further information, please contact:

Dr Jim Salinger – Principal Scientist, Climate NIWA National Climate Centre – Auckland Phone +64 9 375 2053 [email protected]

Dr Jim Renwick – Science Leader NIWA National Climate Centre – Wellington Phone +64 4 386 0343 [email protected]

 

Acknowledgement of NIWA as the source is required.