Halley 12Z 500hPa temperature 1957 - - - -36.0 -39.6 -43.3 -41.5 -41.1 -37.8 -37.8 -33.6 -32.8 1958 -33.4 -32.9 -36.0 -37.4 -41.0 -39.4 -41.6 -41.7 -39.9 -38.4 -35.4 -35.5 1959 -31.0 -33.0 -33.8 -38.9 -36.4 -38.5 -43.0 -40.9 -41.4 -37.9 -38.3 -32.5 1960 -33.5 -32.8 -34.5 -35.6 -38.3 -39.0 -39.1 -41.9 -37.7 -37.4 -35.9 -33.9 1961 -30.4 -33.3 -35.4 -37.2 -36.6 -40.1 -41.0 -40.0 -39.2 -35.7 -33.9 -33.8 1962 -31.8 -32.8 -34.7 -36.5 -36.8 -39.2 -40.2 -40.4 -39.1 -37.0 -34.9 -35.2 1963 -29.4 -34.8 -36.0 -38.8 -37.4 -38.9 -39.9 -38.6 -38.0 -37.8 -35.2 -32.9 1964 -29.2 -31.9 -34.4 -37.0 -40.7 -37.9 -38.4 -42.2 -41.0 -38.1 -34.1 -34.8 1965 -32.5 -33.1 -34.7 -38.0 -36.5 -40.0 -40.0 -39.3 -38.7 -36.8 -34.8 -32.3 1966 -31.9 -30.8 -33.7 -36.0 -36.9 -39.6 -40.7 -41.0 -40.5 -37.7 -34.6 -32.1 1967 -30.1 -33.9 -34.4 -36.9 -36.5 -38.9 -40.9 -40.6 -38.7 -39.1 -38.0 -31.4 1968 -34.2 -31.6 -33.7 -35.1 -36.0 -40.4 -40.3 -40.8 -41.2 -35.1 -34.5 -32.4 1969 -32.5 -33.1 -36.2 -35.7 -38.6 -41.0 -41.6 -40.1 -38.2 -37.8 -36.6 -29.8 1970 -31.5 -32.9 -34.6 -36.1 -36.9 -40.7 -39.0 -40.5 -37.6 -36.0 -34.4 -31.8 1971 -31.5 -33.9 -34.3 -32.8 -39.8 -39.3 -41.4 -38.2 -39.6 -37.5 -35.3 -32.5 1972 -33.2 -32.8 -36.4 -38.2 -36.5 -40.4 -38.7 -39.1 -38.9 -37.6 -33.7 -32.8 1973 -31.6 -33.3 -34.5 -38.1 -37.7 -39.7 -40.1 -39.1 -39.0 -35.8 -35.0 -33.2 1974 -31.8 -32.7 -33.6 -36.6 -39.8 -38.3 -41.3 -39.7 -38.9 -37.5 -35.4 -32.9 1975 -29.8 -32.1 -34.4 -39.2 -38.9 -41.0 -41.0 - - - - -31.3 1976 -31.3 -32.3 -33.2 -35.7 -38.1 -38.2 -40.0 -41.1 -40.6 -39.8 -34.8 -31.1 1977 -32.7 -34.5 -34.4 -33.5 - -37.2 -40.7 -40.7 -41.5 -37.5 -33.7 -35.9 1978 -31.1 -33.6 -33.7 -32.4 -35.7 -38.8 -41.5 -39.8 -39.0 -36.7 -35.0 -33.9 1979 -29.9 -33.4 -32.9 -34.2 -39.1 -39.4 -41.2 -41.4 -38.5 -38.0 -35.6 -31.5 1980 -31.9 -31.3 -35.5 -38.2 -37.9 -39.2 -41.5 -41.4 -38.2 -36.9 -34.6 -33.8 1981 - -31.9 -33.1 -35.5 -37.5 -40.2 -39.6 - - - - - 1982 - - -33.8 -37.0 -36.6 -36.4 -41.6 -41.4 -39.2 -36.7 -34.5 -31.7 1983 -32.1 -31.7 -34.9 -34.7 -34.3 -37.4 -40.5 -39.0 -38.7 -38.0 -34.4 -31.9 1984 - -31.5 -34.2 -35.6 -36.1 -39.3 -38.8 -38.2 -38.5 -37.2 -34.7 -30.1 1985 -29.3 -31.3 -32.7 -36.2 -38.8 -39.3 -38.2 -37.7 -37.1 -36.3 -35.8 -30.8 1986 -29.1 -28.6 -32.3 -34.8 -40.6 -39.3 -37.5 -41.1 -40.3 -38.3 -34.1 -31.4 1987 -30.8 -27.9 -33.8 -35.3 -37.2 -38.1 -39.3 -41.2 -39.6 -37.6 -34.4 -30.8 1988 -30.1 -32.9 -32.4 -36.0 -36.9 -39.2 -39.7 -35.8 -36.0 -35.3 -33.8 -31.6 1989 -29.1 -31.3 -32.3 -38.4 -37.1 -37.2 -37.3 -37.5 -37.9 -36.8 -33.8 -33.2 1990 -30.1 -32.9 -33.5 -36.0 -37.2 -37.5 -39.7 -39.8 -37.9 -35.8 -32.5 -32.1 1991 -30.1 -29.7 -35.7 -34.3 -37.9 -38.4 -39.8 -38.8 -36.2 -36.9 -34.7 -29.1 1992 - -32.6 -37.3 -35.1 -37.8 -40.6 -39.1 -41.7 -38.2 -34.8 -34.7 -30.5 1993 -31.7 -32.6 -34.4 -36.8 -37.9 -39.7 -38.7 -38.3 -40.0 -37.4 -32.0 -32.7 1994 -30.5 -32.8 -33.4 -36.8 -37.9 -38.9 -42.1 -40.3 -37.1 -40.8 -34.3 -33.6 1995 -30.5 -33.1 -33.4 -36.5 -38.1 -37.4 -42.6 -41.5 -39.8 -35.5 -34.2 -31.6 1996 -31.8 -30.0 -33.2 -35.8 -36.3 -38.9 -40.2 -36.0 -39.6 -35.9 -33.3 -31.2 1997 -29.3 -33.5 -33.5 -35.3 -37.9 -39.2 -40.7 -40.1 -40.5 -39.6 -35.7 -32.0 1998 -29.4 -29.6 -33.4 -37.1 -37.9 -36.3 -38.3 -39.1 -38.2 -38.0 -33.9 -31.6 1999 -29.1 -30.2 -33.1 -35.6 -34.0 -38.7 -39.2 -39.5 -39.4 -33.8 -32.3 -32.7 2000 -33.2 -31.8 -32.2 -37.1 -36.7 -38.3 -38.2 -41.2 -41.0 -37.7 -34.5 -34.1 2001 -32.4 -32.1 -35.5 -38.2 -34.8 -40.7 -41.0 -40.4 -36.7 -38.5 -35.4 -32.9 2002 -30.4 -31.6 -33.7 -34.6 -39.3 -40.9 -39.5 -37.7 -37.5 -37.7 -36.9 -31.6 2003 -30.0 -30.8 -33.9 -35.9 -38.6 -40.0 -40.4 -38.0 -37.7 -36.7 -35.8 -31.5 2004 -31.3 -35.0 -32.8 -35.8 -37.2 -38.4 -39.4 -41.4 -36.1 -34.8 -35.0 -31.9 2005 -29.0 -31.6 -32.9 -34.0 -38.3 -41.5 -40.7 -38.7 -37.5 -35.7 -34.4 -32.4 2006 -32.4 -34.0 -30.6 -36.1 -39.3 -37.1 -38.1 -42.2 -39.4 -36.2 -32.9 -33.5 2007 -28.8 -33.5 -34.9 -38.0 -36.1 -37.7 -39.5 -40.1 -38.3 -37.7 -35.7 -32.2 2008 -32.5 -32.5 -34.7 -33.9 -38.8 -39.5 -39.3 -40.2 -35.7 -38.4 -35.6 -34.1 2009 -32.1 -33.0 -32.5 -37.2 -36.9 -38.8 -38.3 -40.2 -39.1 -38.1 -35.3 -32.0 2010 -29.5 -31.5 -34.0 -37.5 -35.2 -36.4 -38.0 -38.3 -36.3 -35.5 -34.7 -31.8 2011 -28.8 -30.5 -33.1 -34.9 -36.9 -39.4 -39.1 -39.1 -38.8 -37.7 -34.6 -34.6 2012 -32.4 -30.0 -32.9 -35.5 -36.7 -39.3 -39.2 -39.7 -38.5 -36.7 -34.1 -30.0 2013 -29.9 -32.8 -33.5 -34.7 -38.6 -36.3 -38.7 -38.3 -36.2 -37.6 -36.1 -30.3 2014 -32.7 -33.0 -34.0 -33.3 -34.8 -38.3 -39.2 - - -36.6 -36.1 -33.0 2015 -33.5 -30.8 -33.2 -35.2 -35.7 -40.2 -39.2 -40.4 -40.6 -37.1 -35.6 -31.2 2016 -31.4 -30.8 -33.7 -35.4 -37.7 -37.7 -40.2 -39.3 -38.3 -36.9 -32.5 -33.5 2017 -31.5 -30.4 - - - - - - - - - -29.9 2018 -32.5 -34.4 - - - - - - - - - -29.6 2019 -31.0 -32.4 - - - - - - - - - -28.9 2020 -29.6 - - - - - - - - - - - 2021 - - - - - - - - - - - -33.6 2022 -28.7 - - - - - - - - - - -33.0 2023 -30.7 - - - - - - - - - - -32.9 2024 -30.6 - - - - - - - - - - -