Syowa 00Z 500hPa temperature 1968 - - -33.7 -36.9 -36.5 -38.7 -43.2 -40.2 -43.9 -36.8 -35.0 -32.5 1969 -30.5 -31.0 -36.0 -35.9 -40.3 -36.3 -42.3 -41.9 -42.2 -36.8 -33.4 -29.8 1970 -32.0 -33.3 -33.6 -37.3 -38.3 -39.7 -41.3 -42.6 -42.2 -39.2 -34.5 -32.1 1971 -29.6 -30.2 -34.6 -38.1 -37.5 -43.1 -42.7 -40.9 -40.3 -40.3 -37.1 -28.8 1972 -30.6 -32.9 -36.6 -35.9 -38.5 -37.6 -43.9 -39.4 -40.4 -39.0 -35.9 -32.2 1973 -31.5 -32.2 -34.3 -36.6 -37.4 -37.7 -43.0 -43.1 -40.9 -39.8 -36.5 -32.9 1974 -29.9 -33.8 -34.3 -37.2 -38.1 -37.1 -41.2 -40.2 -39.9 -40.7 -34.6 -31.4 1975 -29.5 -31.6 -33.3 -38.7 -34.8 -40.3 -38.8 -40.6 -39.9 -40.3 -35.0 -32.0 1976 -28.7 -33.6 -36.0 -38.8 -42.2 -39.1 -42.2 -41.2 -41.5 -42.5 -35.1 -29.6 1977 -31.2 -33.2 -36.3 -37.0 -35.6 -37.5 -36.5 -37.7 -41.4 -39.4 -37.2 -33.3 1978 -34.2 -32.9 -35.7 -38.7 -38.4 -40.6 -40.6 -43.3 -41.0 -38.2 -35.9 -33.2 1979 -30.6 -33.4 -35.0 -34.6 -36.9 -41.6 -41.7 -43.7 -41.4 -38.0 -33.9 -31.2 1980 -32.2 -32.8 -32.7 -36.0 -37.1 -40.4 -36.7 -40.3 -38.2 -40.6 -34.3 -33.4 1981 -30.9 -29.1 -35.3 -38.3 -37.3 -40.1 -37.9 -39.4 -39.0 -39.8 -37.1 -31.4 1982 -30.8 -31.9 -35.7 -36.7 -37.8 -40.4 -41.9 -39.4 -39.8 -38.9 -32.6 -29.4 1983 -31.5 -33.6 -36.0 -35.1 -36.3 -39.9 -41.6 -42.7 -38.7 -38.7 -36.6 -33.8 1984 -32.0 -32.7 -33.5 -37.7 -34.6 -40.3 -39.0 -40.5 -40.9 -39.9 -35.7 -29.7 1985 -30.4 -31.3 -31.9 -35.3 -39.2 -37.5 -40.0 -40.8 -40.5 -39.6 -36.7 -33.4 1986 -30.1 -29.6 -32.3 -36.5 -38.2 -38.5 -40.1 -38.6 -40.3 -39.2 -34.4 -33.7 1987 -30.9 -31.8 -33.9 -36.2 -36.9 -39.3 -39.2 -39.6 -42.0 -38.2 -33.5 -31.8 1988 -28.7 -30.7 -31.2 -37.4 -38.0 -36.5 -41.0 -41.4 -38.0 -37.2 -35.8 -32.3 1989 -29.5 -30.5 -34.2 -37.6 -40.3 -39.3 -41.3 -41.8 -41.7 -39.0 -35.0 -32.6 1990 -31.1 -32.6 -34.9 -35.4 -36.8 -40.7 -36.5 -42.2 -43.7 -36.6 -34.9 -33.3 1991 -32.1 -29.9 -33.7 -38.7 -37.9 -37.4 -41.2 -39.4 -40.5 -38.7 -36.8 -28.3 1992 -28.6 -32.6 -33.0 -36.0 -34.9 -37.2 -39.2 -42.6 -42.1 -39.0 -38.1 -32.0 1993 -29.8 -33.3 -37.0 -37.4 -35.9 -38.6 -39.3 -39.6 -38.2 -37.1 -36.2 -32.3 1994 -33.3 -32.1 -34.5 -34.6 -39.0 -37.3 -38.9 -39.2 -40.9 -38.1 -36.1 -32.4 1995 -31.8 -30.4 -32.9 -35.9 -38.5 -40.2 -38.1 -40.3 -42.3 -37.2 -36.0 -30.9 1996 -32.3 -30.3 -35.5 -35.2 -38.8 -38.3 -36.7 -37.8 -36.4 -38.3 -34.9 -32.2 1997 -30.6 -31.5 -35.2 -36.5 -37.4 -37.1 -39.7 -40.4 -40.3 -38.6 -32.4 -32.0 1998 -31.6 -33.2 -34.2 -36.8 -35.9 -38.5 -39.5 -39.8 -40.7 -39.3 -35.4 -33.4 1999 -30.8 -30.2 -35.9 -39.3 -38.5 -37.5 -41.7 -37.7 -38.5 -38.0 -35.5 -33.6 2000 -33.2 -32.3 -37.5 -35.5 -38.9 -36.4 -39.5 -38.7 -37.8 -38.9 -35.1 -33.1 2001 -31.1 -31.9 -35.0 -35.7 -35.8 -37.0 -37.0 -42.2 -41.3 -38.8 -36.4 -33.7 2002 -31.3 -32.1 -32.7 -33.2 -34.2 -37.2 -37.4 -39.0 -41.1 -34.7 -37.4 -31.2 2003 -31.3 -32.0 -33.6 -36.1 -37.5 -40.9 -41.0 -40.6 -40.0 -38.8 -33.2 -30.4 2004 -30.3 -30.5 -33.6 -37.6 -39.9 -39.2 -42.7 -42.3 -41.1 -38.6 -37.0 -32.5 2005 -32.2 -33.3 -32.8 -36.0 -38.8 -39.5 -39.1 -39.7 -41.2 -39.4 -37.5 -30.8 2006 -31.5 -32.4 -34.8 -37.0 -36.8 -37.1 -40.9 -36.4 -39.5 -39.3 -33.4 -33.5 2007 -31.0 -32.4 -34.8 -35.2 -36.1 -36.2 -37.4 -39.2 -39.8 -37.3 -31.6 -33.9 2008 -33.1 -34.1 -32.7 -32.8 -36.9 -39.2 -38.0 -42.2 -39.4 -38.9 -36.1 -33.6 2009 -30.9 -32.5 -32.0 -38.1 -32.8 -33.3 -37.3 -40.6 -39.8 -37.0 -32.7 -31.8 2010 -29.8 -30.1 -33.7 -36.8 -39.7 -41.3 -39.6 -41.4 -39.3 -39.8 -36.1 -31.7 2011 -29.4 -31.2 -33.2 -34.0 -36.6 -35.1 -39.8 -38.0 -38.5 -37.7 -34.8 -32.8 2012 -31.8 -29.6 -35.6 -36.6 -36.5 -41.1 -39.7 -38.7 -40.2 -35.6 -31.0 -30.6 2013 -28.5 -30.5 -34.7 -37.6 -38.7 -37.3 -41.3 -38.7 -38.9 -39.5 -32.1 -31.4 2014 -31.2 -31.4 -34.7 -39.6 -36.9 -38.9 -40.6 -38.1 -39.9 -38.4 -36.0 -32.1 2015 -31.0 -32.2 -34.0 -38.8 -36.4 -39.0 -41.7 -41.4 -40.2 -36.6 -32.3 -33.9 2016 -31.7 -31.4 -31.8 -33.0 -36.5 -39.9 -40.9 -35.9 -39.2 -35.3 -34.0 -30.5 2017 -30.0 - -35.2 -37.8 -36.0 -43.0 -38.4 -41.0 -39.9 - - - 2018 -31.0 -30.4 -32.8 -36.0 -35.4 -36.2 -41.7 -39.5 -39.3 -37.1 - -33.0 2019 -30.0 - - -36.3 - -38.2 -39.8 -42.5 -40.3 -32.5 - - 2020 - -32.6 - -33.6 -35.4 -37.6 -39.5 -40.5 -38.6 -39.9 -34.8 - 2021 -32.9 -35.4 -27.4 -34.8 -39.9 -39.0 -41.4 -41.5 -38.6 -38.1 -33.2 -31.7 2022 -29.5 -30.7 -31.3 -34.3 -37.6 -37.1 - -40.1 - -36.5 -35.9 - 2023 - - -30.9 -35.2 -37.2 -37.9 -39.0 -39.7 - -34.9 -34.3 -30.5 2024 -30.3 -30.3 -33.5 -35.3 - - - - - - - -