A hot year, but above all wet
2018 was the second-warmest year on record. By the numbers
The weather in 2018 set records in South Canterbury but for most it will be remembered as wet.
Annual climate figures from the National Institute of Water and Atmospheric Research (Niwa) show Timaru’s annual rainfall total of 858 millimetres was the fourth-highest recorded in the town since records began in 1881 and 159 per cent more than normal.
Oamaru recorded its wettest spring on record. On November 8, it recorded 52mm of rain – its highest one-day rainfall since records began in 1950.
Other highest one-day rainfalls recorded were at Orari Estate and Timaru Airport on April 28, recording 96mm and 85mm respectively with these records beginning in 1897 and 1881 respectively.
In a year of extremes, 2018 was also the second-warmest year on record for New Zealand with Oamaru’s temperature reaching 33.8 degrees Celsius on January 31 – its highest daily maximum temperature on record since 1967.
Mt Cook Airport, on October 23, also set a new highest daily maximum temperature of 26.1C while on February 16, Aoraki/Mt Cook recorded 32.1C, its third highest temperature since records began in 1929.
When it came to cold, Mt Cook Airport featured again with the country’s lowest temperature of -10.4C on June 3, and on October 13 the village recorded its lowest daily minimum ever for that month of -7.5C which was a day after it recorded its equal lowest daily maximum of 1.1C.
Oamaru also set some new low daily maximum temperature records for February of 10.2C on the 21st and 9C on March 22.
During spring, soils remained wetter than normal in South Canterbury.
The Niwa report says that during spring, easterly wind flows brought wetter than normal conditions to the eastern South Island, particularly in November when there heavy rainfall.
On November 8 and 9, persistent was widespread heavy rain fell in the region and again on November 19 and 20, causing surface flooding.
Lowest New Zealand 2018 temperature: -10.4C, Aoraki/Mt Cook Airport. Fourth-highest average temperature (since 1967): Oamaru, 11.4C. Highest minimum temperatures: Aoraki/Mt Cook (4.6C), and Orari Estate (6.1C). Third-highest extreme maximum temperature (since 1929): Aoraki/Mt Cook, 32.1C on February 16. Second-lowest extreme minimum temperature (since 1972): Oamaru, 18.6C on January 29. Fourth-highest rainfall (since 1881): Timaru, 858mm. Highest one-day rainfall: Orari Estate, 96mm; Timaru Airport, 85mm; Oamaru, 52mm. Highest maximum temperatures: Oamaru, 33.8C on January 16 and Aoraki/Mt Cook on October 23, 26.1C. Low daily maximum temperatures: Oamaru, 10.2C on February 21 and 9C on March 22; Aoraki/Mt Cook, 1.1C on October 12. Extremes of low daily minimum temperatures: Aoraki/Mt Cook Airport, -7.5 on October 13.