| Year | Max Depth (cm) | Date |
|---|---|---|
| 2007 | none | – |
| 2006 | none | – |
| 2005 | 14.0 | January 10 |
| 2004 | 23.0 | January 31 |
| 2003 | 27.0 | March 11 |
| 2002 | 19.0 | December 22 |
| 2001 | 33.0 | February 24 |
| 2000 | 31.0 | December 28 |
| 1999 | 29.0 | January 28 |
| 1998 | 28.0 | January 26 |
| 1997 | 33.0 | February 22 |
| 1996 | 28.0 | December 30 |
| 1995 | 52.0 | March 6 |
| 1994 | 42.0 | February 23 |
| 1993 | 33.0 | January 14 |
| 1992 | 46.0 | January 27 |
| 1991 | 46.0 | December 14 |
| 1990 | 34.0 | March 16 |
| 1989 | 24.0 | January 3 |
| 1988 | 16.0 | February 7 |
| 1987 | 12.0 | March 19 |
| 1986 | 29.0 | February 17 |
| 1985 | 49.0 | February 26 |
| 1984 | 38.0 | December 29 |
| 1983 | 30.0 | March 7 |
| 1982 | 22.0 | February 9 |
| 1981 | 8.0 | December 27 |
| 1980 | 34.0 | March 15 |
| 1979 | 32.0 | March 14 |
| 1978 | 44.0 | January 14 |
| 1977 | 37.0 | December 29 |
| 1976 | 38.0 | March 13 |
| 1975 | 53.0 | April 8 |
| 1974 | 69.0 | February 13 |
| 1973 | 25.0 | December 17 |
| 1972 | 58.0 | March 7 |
| 1971 | 58.0 | January 16 |
| 1970 | 61.0 | March 8 |
| 1969 | 53.0 | February 27 |
| 1968 | 53.0 | January 18 |
| 1967 | 71.0 | March 13 |
| 1966 | 61.0 | February 14 |
| 1965 | 64.0 | March 1 |
| 1964 | 79.0 | January 23 |
| 1963 | 46.0 | December 27 |
| 1962 | 71.0 | March 12 |
| 1961 | 48.0 | March 4 |
| 1960 | 64.0 | March 10 |
| 1959 | 58.0 | February 16 |
| 1958 | 48.0 | December 28 |
| 1957 | 74.0 | March 12 |
| 1956 | 114.0 | April 1 |
| 1955 | 62.0 | March 23 |