HIGHLIGHT: The seasonal mean NINO3.4 anomaly was about 0.0 C for NDJ2012/13, further down from OND2012 (0.2).

The CA method, acting on global NDJ2012/13 seasonal means as latest input, but using a string of global SST going back one year, has all of its members staying in the neutral zone for a long time. A few members are in weak negative territory by JAS 2013 but no members below -0.7.

Weights have changed some from last month, but with an ill-defined initial condition it is hard for weight to be large and/or stable. Bigger changes may occur next month when one year of data is added and the covariance matrix increases in size from 56X56 to 57X57.

OCN flavor is much reduced compared to a few years ago, but not completely gone.

Table 1. Inner products (IP; scaled such that the sum of absolute values is 100; not shown) and weights (Wgt multiplied by 100.) of each of the years to construct an analogue to the sequence of 12 consecutive overlapping 3-month periods defined as the base (currently the 12 overlapping seasons string DJF2012 thru NDJ2012). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2011 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2011). Data currently thru January 2013.

Year	IP	Wgt	Year	IP	Wgt	Year	IP	Wgt	Year	IP	Wgt	Year	IP	Wgt	Year	IP	Weigt
1956	xx	3	1966	xx	-2	1976	Xx	3	1986	xx	-15	1996	xx	-6	2006	xx	6
1957	xx	5	1967	xx	0	1977	Xx	7	1987	xx	-11	1997	xx	-4	2007	xx	4
1958	xx	-6	1968	xx	-8	1978	Xx	1	1988	xx	-13	1998	xx	-8	2008	xx	5
1959	xx	-5	1969	xx	6	1979	Xx	2	1989	xx	0	1999	xx	4	2009	xx	7
1960	xx	2	1970	xx	-2	1980	Xx	-1	1990	xx	5	2000	xx	7	2010	xx	-2
1961	xx	1	1971	xx	-2	1981	Xx	-2	1991	xx	-8	2001	xx	7	2011	xx	9
1962	xx	4	1972	xx	1	1982	Xx	-4	1992	xx	-2	2002	xx	6	2012	xx	NA
1963	xx	8	1973	xx	-8	1983	xx	7	1993	xx	-6	2003	xx	-4		xx	Xx
1964	xx	-5	1974	xx	-5	1984	Xx	7	1994	xx	12	2004	xx	-4		xx	Xx
1965	xx	-3	1975	xx	-2	1985	Xx	-7	1995	xx	3	2005	xx	13		xx	Xx

Weights are high +ve (>+0.10) for 2005, 1994

Weights are high -ve (< - 0.10) for 1988,1987,1986

Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):

-0.01	-0.03	-0.11	-0.22	-0.22	-0.16	-0.11	-0.1	-0.19	-0.28	-0.25	-0.19	-0.15	-0.14	-0.17	-0.18	-0.08	0.1	0.32	0.48	0.48
NDJ		JFM13		MAM		MJJ		JAS		SON13		NDJ		JFM14		MAM		MJJ		JAS

One month ago:

0.18	0.2	0.16	0.05	-0.02	-0.03	-0.02	-0.02	-0.06	-0.18	-0.27	-0.24	-0.16	-0.14	-0.14	-0.15	-0.12	0.02	0.19	0.34	0.41
	NDJ		JFM13		MAM		MJJ		JAS		SON13		NDJ		JFM14		MAM		MJJ

Two months ago

0.38	0.43	0.51	0.45	0.31	0.18	0.08	0	-0.07	-0.18	-0.34	-0.47	-0.5	-0.6	-0.5	-0.42	-0.34	-0.25	-0.07	0.15	0.33
SON12		NDJ		JFM13		MAM		MJJ		JAS		SON13		NDJ		JFM14		MAM		MJJ

Three months ago:

0.49	0.52	0.62	0.66	0.49	0.33	0.17	0.01	-0.11	-0.16	-0.24	-0.37	-0.54	-0.67	-0.66	-0.57	-0.48	-0.4	-0.33	-0.2	0.02
	SON12		NDJ		JFM13		MAM		MJJ		JAS		SON		NDJ		JFM14		MAM

Four months ago

0.65	0.63	0.69	0.8	0.75	0.58	0.41	0.19	-0.01	-0.14	-0.16	-0.22	-0.32	-0.64	-0.68	-0.69	-0.64	-0.6	-0.53	-0.44	-0.32
JAS		SON2012		NDJ		JFM2013		MAM		MJJ		JAS		SON		NDJ		JFM2014		MAM

Anomalies relative to 1981-2010 climo, as of the May 2011 release. Older forecasts (previous to May 2011 release) are relative to 71-2000