January = 40.0 at Timaru (22 January 1908)
February = 42.4 at Rangiora (7 February 1973)
March = 36.0 at Ashburton (1 March 1956)
April = 31.4 at Fairlie (1 April 1952)
May = 29.7 at Lincoln (6 May 1972)
June = 25.7 at Hastings (10 June 2024)
July = 23.9 at Hastings (8 July 1942)
August = 26.3 at Cheviot (31 August 2007)
September = 31.1 at Lincoln (24 September 1924)
October = 32.8 at Timaru (10 October 1914)
November = 35.6 at Lake Coleridge (26 November 1920)
December = 36.9 at Lincoln (4 December 1869)