| Rank | Precipitation | Month |
|---|---|---|
| 1 | 17.6 inches | July 1992 |
| 2 | 16.7 inches | May 2019 |
| 3 | 15.7 inches | July 1948 |
| 4 | 15.5 inches | June 2007 |
| 5 | 15.3 inches | May 1943 |
| 6 | 15.0 inches | August 2019 |
| 7 | 14.2 inches | September 1926 |
| 8 | 13.6 inches | May 1982 |
| 9 | 13.5 inches | April 1994 |
| 10 | 13.4 inches | September 1941 |
| 11 | 13.2 inches | May 1995 |
| 12 | 13.2 inches | September 1915 |
| 13 | 13.0 inches | October 1986 |
| 14 | 12.8 inches | June 2021 |
| 15 | 12.7 inches | September 1973 |
| 16 | 12.3 inches | September 1961 |
| 17 | 12.1 inches | May 1935 |
| 18 | 11.8 inches | June 1951 |
| 19 | 11.7 inches | May 1990 |
| 20 | 11.6 inches | June 1967 |