Marion 12Z 500hPa temperature 1966 - - - - - - - - -24.8 -23.7 - - 1967 - - - - -20.7 -24.8 -26.7 -23.7 -25.9 - -24.0 - 1968 - - - - - - - - -25.3 - -24.1 -23.2 1969 -18.8 - - - - -24.0 -23.5 - -29.2 -23.6 -23.4 -24.1 1970 -18.7 - - -24.4 -21.6 -23.8 -25.5 -26.7 -27.7 -22.9 -25.1 -18.9 1971 - -14.8 -17.3 -23.1 -25.2 -23.3 -24.2 -25.3 -25.6 -23.1 -21.6 -22.8 1972 -18.2 -17.6 -16.4 -19.9 -24.9 -21.8 -26.9 -24.7 -24.7 - -17.8 - 1973 - -15.7 -19.8 -18.3 -26.0 -25.7 -23.5 -26.8 -25.5 - - -18.2 1974 -18.3 -16.4 -17.0 -21.4 -20.5 -22.5 -24.3 -24.5 -22.9 -21.1 -21.0 -17.7 1975 -18.5 -16.6 -16.9 -17.7 -22.6 -23.5 -29.1 -28.2 -25.0 -22.9 -23.2 -20.1 1976 -19.5 -17.1 -19.0 -21.1 -21.6 -23.3 -26.6 -27.5 -22.9 -24.0 -24.2 -20.9 1977 -19.0 -15.6 -16.7 -21.4 -22.1 -24.7 -25.1 -26.7 -23.3 -22.0 -21.2 -19.2 1978 -18.4 -20.0 -17.3 -19.0 -23.1 -23.6 -23.5 -25.6 -24.2 -22.7 -22.8 -18.2 1979 -18.2 -16.8 -17.4 -19.4 -23.3 -23.0 -24.1 -25.0 -26.6 -23.6 -22.2 -20.9 1980 -18.7 -16.6 -16.9 -19.8 -20.9 -25.1 -24.4 -24.2 -25.7 -24.2 -22.9 -20.1 1981 -19.1 -13.9 -17.1 -20.5 -20.1 -24.3 -23.8 -25.1 -23.7 -22.4 -20.5 -20.0 1982 -18.6 -17.1 -17.4 -17.8 -22.1 -21.6 -24.9 -23.7 -23.7 -22.6 -22.1 -21.0 1983 -19.8 -16.5 -17.7 -18.4 -18.9 -24.2 -25.3 -26.0 -22.2 -22.2 -20.0 -18.8 1984 -18.1 -15.4 -17.6 -19.3 -23.5 -23.8 -25.1 -25.4 -25.2 -20.2 -20.8 -21.8 1985 -17.1 -16.4 -16.8 -17.2 -22.9 -24.0 -23.6 -24.8 -24.1 -21.8 -18.5 -19.3 1986 -18.1 -17.3 -19.1 -19.7 -22.4 -24.0 -23.9 -22.9 -22.5 -20.9 -20.7 -17.9 1987 -18.9 -16.0 -18.1 -19.6 -21.2 -23.8 -22.8 -25.2 -25.6 -22.2 -22.2 -21.3 1988 -19.1 -16.7 -17.8 -18.4 -24.2 -23.7 -27.5 -27.0 -26.4 -26.1 -21.0 -20.9 1989 -17.6 -15.3 -15.3 -21.0 -22.5 -25.7 -24.3 -26.0 -25.4 -23.9 -20.2 -17.9 1990 -16.8 -15.4 -17.3 -18.0 -24.5 -26.9 -25.5 -25.6 -22.9 -23.4 -21.5 -20.2 1991 -18.3 -17.6 -16.8 -20.2 -21.2 -23.3 -25.5 -26.8 -24.3 -22.0 -22.1 -19.0 1992 -20.2 -15.5 -15.5 -19.4 -24.5 -25.4 -26.5 -25.9 -26.1 -22.9 -20.8 -22.6 1993 -21.3 -14.7 -17.0 -18.9 -24.2 -24.1 -25.6 -25.1 -24.6 -22.4 -20.2 -19.9 1994 -18.6 -15.5 -16.4 -19.1 -22.0 -25.2 -25.6 -27.5 -24.1 -24.4 -24.3 -19.0 1995 -16.4 -18.1 -18.3 -22.9 -22.2 -25.6 -27.9 -24.1 -23.0 -23.5 -21.7 -17.9 1996 -18.6 -17.3 -17.5 -18.3 -20.5 -25.6 -25.4 -25.1 -25.5 -23.1 -22.0 -20.2 1997 -17.8 -16.0 -18.6 -19.4 -20.4 -24.3 -24.2 -25.5 -22.3 -23.3 -21.9 -19.8 1998 -18.9 -19.8 -18.1 -19.9 -22.3 -26.3 -25.6 -24.8 -26.7 -22.5 -19.9 -18.7 1999 -17.4 -18.0 -18.0 -19.8 -23.5 -25.5 -24.9 -24.7 -24.8 -21.9 -21.6 -18.3 2000 -18.3 -17.5 -18.1 -21.2 -23.4 -24.4 -25.1 -27.1 -28.5 -22.0 -19.3 -23.7 2001 -17.3 -15.5 -17.0 -19.6 -22.2 -24.3 -23.2 -26.0 -24.5 -22.7 -21.5 -19.6 2002 -17.8 -16.9 -18.1 -17.1 -21.9 -25.1 -26.2 -22.6 -25.3 -22.8 -22.0 -19.3 2003 -20.8 -17.3 -17.0 - - - - - - - -21.3 -20.8 2004 -18.7 -17.1 -18.8 -18.9 -23.7 -21.8 -25.7 -27.1 -23.2 -22.1 -23.7 -18.7 2005 -20.2 - - -20.2 -22.1 -24.4 -25.6 -25.2 -24.6 -21.0 -19.4 -25.6 2006 -19.8 -17.5 -19.5 -21.7 - - - - -25.2 -22.4 -22.9 -22.0 2007 -19.1 -14.8 -16.1 -18.5 -25.3 -22.6 -26.7 -26.3 -25.8 -23.1 -22.7 -17.6 2008 -18.5 -17.9 -18.1 -21.8 -21.5 -23.3 -26.4 -26.3 -26.3 -25.5 -21.3 -19.9 2009 -18.1 -17.0 -18.3 -19.8 -20.2 -22.4 -25.9 -24.2 -27.2 -20.0 -19.1 -22.1 2010 -18.0 -16.2 -19.2 -21.9 -24.3 -23.8 -24.8 -23.7 -24.6 -24.2 - - 2011 - - - -20.6 -21.1 -24.3 -26.9 -22.8 -27.0 -23.2 -23.3 -18.9 2012 -17.1 -18.6 -17.5 -19.2 -23.4 -25.6 -24.8 -21.5 - - - - 2013 -20.3 -16.9 -17.0 - - - - - - - - - 2014 - - - -23.4 - - - - - - - - 2015 - - - - - - - - - - - - 2016 - - - - -21.6 -24.3 -24.0 -24.1 -24.6 -22.8 -23.8 -22.6 2017 -17.2 -17.8 -18.4 -17.9 -20.9 -27.8 -26.5 -26.8 -26.2 -22.5 -19.8 -21.2 2018 -17.2 -17.1 -19.2 -19.7 -21.8 -24.0 -23.1 -27.9 -25.4 -19.7 -20.9 -19.1 2019 -18.5 -17.2 -18.1 -19.3 -21.4 -23.7 -26.0 -27.8 -24.5 -24.7 -25.1 -20.3 2020 -18.9 -16.4 -18.1 -20.7 - - - - - - - - 2021 - - - - - - - - - - - - 2022 - - - - - - - - - - - - 2023 - - - - -22.7 -26.4 -27.3 -23.9 - -23.1 -21.0 -16.8 2024 -16.4 -15.1 -17.1 -18.3 - - - - - - - -