About a week short of the end of last month, the Otago Daily Times reported a weather station at Balaclava had already broken its 34-year record of 164mm.
The station recorded the total for the month of 214mm - about three times the 72mm average.
National Institute of Water and Atmospheric Research's statistics for May have now shown just how wet it was.
Many towns throughout Otago received about double the normal May rainfall and average daily temperatures were between 1.5degC and 2.5degC colder than normal.
Niwa climate scientist Andrew Tait said it was cold around the whole country in May.
Storms made it wetter than usual in Otago, Canterbury, Wairarapa and Northland.
Records were reached throughout Otago during the month.
Dunedin, with its combined reading of 168mm, saw its the fourth highest since records began in 1918 and more than double its average rainfall.
Ranfurly's 65mm was also the fourth highest since the town's records began in 1943 and double its average.
Balclutha, recorded 113mm, nearly double its average and the third highest rainfall since records began in 1964.
Dunedin's combined recording of its mean daily temperature, 7.4degC, was the fourth lowest since 1947 and the airport's 6.2degC, the lowest since 1947.
Queenstown recorded its second lowest temperature for May since 1971, with 4.8degC.
Wanaka also had its second-lowest temperature since its records began in 1955 with 4.9degC, as did Balclutha, with 5.9degC, 2.2degC cooler than normal, its second lowest since 1964.
The only sunshine figure available yesterday showed Musselburgh in Dunedin received normal sunshine hours for May with 100 hours.