Dunedin has an equable climate. The average annual rainfall is 31 in. on the flat, with a slight increase in the hilly suburbs. There is an even spread through the year averaging 2½–3 in. per month. The most settled period is from February to April, but sudden weather changes are associated with the passage of cold fronts, which are usually followed by a spell of showery, south-westerly weather. Winds are mostly from between north-west and south-west; north-easterlies are also very frequent and at times are accompanied by mist or fog. Rain days (0.01 or more) average 162 per annum, and on 75 of these the rainfall reaches 0.1 in.

The warmest months are January and February, with mean temperature 59°F; July (44°F) is the coldest. In January the mean daily maximum and minimum temperatures are, respectively, 67°F and 52°F; in July the daily range is from 50°F to 37°F. Air temperature rises above 80°F on four days a year and falls below 32°F (screen frosts) on 12 days. Ground frosts are much more numerous—about 90 on the flat, but fewer on sunny slopes. A few inches of snow may cover the city briefly once or twice a year, but many winters are virtually snow free. The worst fall on record covered most of Dunedin to a depth of 12 in. on 26 July 1939. Hail falls on about 10 days per annum, but causes negligible damage; thunderstorms are about half as frequent. The average duration of sunshine is 1,730 hours per annum, and it is close to 39 per cent of the possible amount in each month, except in December, when it attains only 34 per cent of the possible.