MEI Ranks (current update: 7 December 2018) Bimonthly ranks of the MEI, since the beginning of record in Dec1949/Jan1950. If two MEI values are identical within the same bimonthly season, their rank is split between them, leading to a ".5" value. Missing values are left blank. How can one interpret these ranks? Given that there are 68 (69) numbers in each column, the lowest number (1) would denote the strongest La Nina case for that bimonthly season, while the highest number (68 or 69) would indicate the strongest El Nino case. For instance, in December-January (DECJAN), the strongest La Nina was recorded in 1974, while the strongest El Nino occurred in 1983. If we use percentiles (say, the lower and upper 30%iles) to define La Nina and El Nino, respectively, MEI ranks from 1-21 denote strong to weak La Nina conditions, while 48-68 (49-69) denote weak to strong El Nino conditions. If one uses the quintile definition for (moderate or stronger) ENSO events, MEI ranks from 1-14 would denote La Nina, while 55-68 (56-69) would denote El Nino. Finally, the comparison figures on this website refer to strong ENSO events, such as might be defined by the top 7 (upper decile) ranks, such as 1-7 for La Nina, and 62-68 (63-69) for El Nino. YEAR DECJAN JANFEB FEBMAR MARAPR APRMAY MAYJUN JUNJUL JULAUG AUGSEP SEPOCT OCTNOV NOVDEC 1950 11 10 6 7 3 5 5 10 15 22 10 6 1951 9 9 8 19 18 39 49 56 52 52 49 46 1952 48 40 38 38 21 11 21 20.5 41 42 24 35 1953 39 46 47 58 54 36 39 39 46 37 38 40 1954 37 39 44 16 2 2 4 5 11 7 11 10 1955 15 19 9 2 1 1 1 1 3 3 1 1 1956 4 6 5 5 5 3 6 9 7 5 15 11 1957 14 28 40 42 56 48 57 62 63 62 60 61 1958 64 63 63 63 51 52 50 45 36 41 43 52 1959 50 54 52 37 28 27 29 34 34 31 29 29 1960 31 31 30 28 20 17 19 26 22 26 26 25 1961 35 32 32 31 22 22 23 24 27 20 21 18 1962 8 12 17 8 9 8 13 14 19 18 18 24 1963 16 14 18 14 14 25 43 47 53 53 55 53 1964 56 49 25.5 18 6 6 3 4 8 10 8 15 1965 23 29 24 33 44 54 63 64 64 63 65 62 1966 63 61 55 52 24 21 28 37 33 32 37 31 1967 27 13 11 9 15 19 15 19 17 17 22 26 1968 19 16 19 10 7 9 14 31 38 45 47 43 1969 52 56 50 55 52 50 45 40 35 48 48 45 1970 46 47 46 30 25.5 13 11 11 9 11 12 7 1971 5 3 1 1 4 4 7 8 6 6 6 12 1972 21 27 25.5 24 42 58 66 66 65 65.5 66 65 1973 65 64 58 51 25.5 10 10 6 4 4 3 2 1974 1 1 2 3 8 12 12 13 16 12 7 16 1975 24 22.5 14 11 10 7 2 2 2 1 2 3 1976 3 5 7 6 13 37 48 51 61 55 44 47 1977 49 42 42 54 37 41 54 52 56 58 57 54 1978 55 57 59 36 17 14 18 27 25 33 40 44 1979 51 45 35 40 41 42 41 49 55 51 51 56 1980 53 52 54 60 59 55 53 42 39 40 41 37.5 1981 34 35 49 57 31 29 31 32 37 38 36 33 1982 33 36 39 29 43 56 64 65 66 67 68 68 1983 69 69 69 69 69 68 65 63 44 35 32 32 1984 29 25 43 44 30 28 30 28 31 34 25 19 1985 22 22.5 16 20 11 23 27 22 20 30 34 28 1986 30 33 37 25 40 38 42 55 62 57 56 59 1987 62 62 65 65 67 66 67 67 67 65.5 62 63 1988 59 53 51 43 32 15 8 7 5 8 5 5 1989 7 7 12 15 16 18 17 16 26 27 33 39 1990 41 51 60 49 49 45 34 35 43 43 42 41.5 1991 42 43 48 47 53 61 58 59 54 60 61 64 1992 66 66 67 67 66 65 59 46 47 50 46 50 1993 54 60 61 64 65 64 62 60 60 61 54 49 1994 45 41 45 50 48 51 55 54 59 64 64 60 1995 61 59 57 48 47 44 36 29 24 21 20 23 1996 20 24 28 23 27 33 25 20.5 23 25 31 27 1997 26 21 27 53 61 69 69 69 69 69 69 67 1998 68 68 68 68 68 63 40 23 14 15 13 14 1999 10 11 13 12 12 16 16 12 12 13 14 9 2000 6 8 10 22 35 31 26 30 28 23 17 21.5 2001 25 20 20 27 36 32 37 43 29 28 30 36 2002 38 34 29 45 58 57 51 58 58 59 58 58 2003 60 58 56 46 34 34 35 41 45 49 45 41.5 2004 44 44 33 41 46 40 47 50 50 47 53 51 2005 43 55 62 56 57 47 46 44 40 29 23 21.5 2006 28 26 21 17 29 46 52 53 57 56 63 55 2007 57 50 41 32 39 24 22 18 10 9 9 8 2008 12 4 4 13 19 35 33 25 18 16 19 17 2009 17 17 15 26 38 49 60 61 51 54 59 57 2010 58 65 64 62 50 20 9 3 1 2 4 4 2011 2 2 3 4 23 30 24 15 13 14 16 13 2012 13 18 23 35 55 53 61 48 42 36 39 37.5 2013 40 37 34 34 33 26 20 17 30 39 35 30 2014 32 30 36 39 60 60 56 57 49 44 52 48 2015 47 48 53 61 63 67 68 68 68 68 67 66 2016 67 67 66 66 64 62 38 38 32 24 28 34 2017 36 38 31 59 62 59 44 33 21 19 27 20 2018 18 15 22 21 45 43 32 36 48 46 50 Next update: This is the final update for the MEI in its present incarnation Link to numerical MEI values is here. Go back to MEI homepage.