Since 1897 (and excluding 1916-18) here are the 10 wettest and driest footy seasons using the rainfall totals from the Adelaide weather stations - West Terrace until 1976 and Kent Town from 1977. The West Terrace station closed in 1980.
The rainfall figures are the total from April to September. Although of course in the earlier seasons, the season started in May, but I wanted to keep the months same throughout.
There are a number of variables, one is which that this rainfall doesn't indicated when during each week it fell, so it may not have had as much (or made more) impact than the figures show.
Also, the different venues - rainfall totals if kept at all league grounds would vary.
But this exercise was to give a rough idea only, and as you'll see, the years that do feature probably doesn't surprise:
Wettest Seasons
Year mm
1923 599.3
1992 544.4
1956 543.1
1909 517.7
1942 517.1
1971 514.3
1981 502.8
2001 498.8
1983 495.6
1932 483.8
Driest Seasons
Year mm
1959 139.0
1914 155.9
1967 175.4
1976 187.4
2006 193.6
1913 202.4
1949 205.5
1994 222.0
1977 225.8
1902 243.4
The year not seen in the wettest table would surprise (1968) had 365.8mm of rain between April and September. This would be an example I would imagine of when that rain fell, not so how much.