MEI Ranks (current update: 7 October 2017)

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 67-68 numbers in each column, the lowest
number (1) would denote the strongest La Nina case for that bimonthly season, while the highest
number (67 or 68) 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 47-67 (48-68) 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 54-67 (55-68) 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 61-67 (62-68) for El Nino.

YEAR    DECJAN  JANFEB  FEBMAR  MARAPR  APRMAY  MAYJUN  JUNJUL  JULAUG  AUGSEP  SEPOCT  OCTNOV  NOVDEC
1950	10	10	6	7	3	5	5	10	17	21	9.5	6
1951	9	9	8	19	18	39	48	55	51	50	48	45
1952	46	39	37	37	21	11	21	20.5	41	41	25	33
1953	38	45	46	56	54	36	38	38	47	36	37	39
1954	36	38	43	16	2	2	4	5	11	7	11	10
1955	15	17	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	27	38	40	55	47	56	61	62	60	58	60
1958	63	62	62	61	51	51	49	44	36.5	40	42	51
1959	49	53	51	36	28	27	29	34	34	30	28	28
1960	30	29	29	27	20	17	19	26	22	24	26	24
1961	34	31	30	29	22	22	23	24	27	19	21	18
1962	8	12	16	8	9	8	13	14	19	18	18	23
1963	16	14	18	14	14	25	42	46	52.5	51	53	52
1964	55	48	24.5	18	6	7	3	4	8	9	8	14
1965	22	28	23	32	44	53	62	63	63	61	63	61
1966	62	60	53	51	24	21	28	36	33	31	36	30
1967	26	13	11	9	15	18	15	19	14	17	22	25
1968	18	15	19	10.5	7	9	14	31	38	43	46	40
1969	51	55	48	54	50	50	44	39	35	46	47	44
1970	45	46	45	28	25	13	11	11	9	11	13	7
1971	5	3	1	1	4	4	7	8	6	6	6	12
1972	20	25.5	24.5	23	42	57	65	65	64	63	64	64
1973	64	63	57	49.5	26	10	10	6	4	4	3	2
1974	1	1	2	3	8	12	12	13	16	12	7	16
1975	23	21	14	10.5	10	6	2	2	2	1	2	3
1976	3	4	7	6	13	38	47	50	60	53	43	46
1977	48	41	41.5	53	37	41	53	51	55	56	55	53
1978	54	56	58	35	17	14	18	27	25	32	39	43
1979	50	44	34	38	41	42	40	48	54	49	49	55
1980	52	51	54	59	58	54	52	41	39	39	40	36
1981	33	34	49	57	30.5	29	31	32	36.5	37	35	32
1982	32	35	39	30	43	56	63	64	65	65	66	67
1983	68	68	68	68	68	67	64	62	45	34	31	31
1984	28	24	41.5	41	30.5	28	30	28	32	33	24	19
1985	21	22	17	20	11	23	27	22	20	29	33	27
1986	29	32	36	25	40	37	41	54	61	55	54	58
1987	61	61	64	64	66	65	66	66	66	64	60	62
1988	58	52	50	43	32	15	8	7	5	8	5	5
1989	7	7	12	15	16	19	17	16	26	26	32	38
1990	40	50	59	47.5	48	43	33	35	43	42	41	41
1991	41	42	47	46	52	61	57	58	52.5	58	59	63
1992	65	65	66	66	65	64	58	45	46	48	45	49
1993	53	59	60	63	64	63	61	59	59	59	52	48
1994	44	40	44	49.5	47	49	54	53	58	62	62	59
1995	60	58	56	47.5	46	44	35	29	24	20	20	22
1996	19	23	27	22	27	33	25	20.5	23	25	30	26
1997	25	20	26	52	60	68	68	68	68	67	67	66
1998	67	67	67	67	67	62	39	23	15	15	12	15
1999	11	11	13	12	12	16	16	12	12	13	14	9
2000	6	8	10	21	35	31	26	30	28	22	17	21
2001	24	19	20	26	36	32	36	42	29	27	29	35
2002	37	33	28	44	56	55	50	57	57	57	56	57
2003	59	57	55	45	34	34	34	40	44	47	44	42
2004	43	43	33	42	45	40	46	49	48	45	51	50
2005	42	54	61	55	57	46	45	43	40	28	23	20
2006	27	25.5	21	17	29	45	51	52	56	54	61	54
2007	56	49	40	31	39	24	22	18	10	10	9.5	8
2008	12	5	3	13	19	35	32	25	18	16	19	17
2009	17	16	15	24	38	48	59	60	50	52	57	56
2010	57	64	63	62	49	20	9	3	1	2	4	4
2011	2	2	4	4	23	30	24	15	13	14	16	13
2012	13	18	22	34	53	52	60	47	42	35	38	37
2013	39	36	32	33	33	26	20	17	30	38	34	29
2014	31	30	35	39	59	59	55	56	49	44	50	47
2015	47	47	52	60	62	66	67	67	67	66	65	65
2016	66	66	65	65	63	60	37	37	31	23	27	34
2017	35	37	31	58	61	58	43	33	21

Next update:  10 November 2017 (or earlier)

Link to numerical MEI values is here.

Go back to MEI homepage.