HIGHLIGHT: The seasonal mean NINO3.4 anomaly was 2.4 C for SON2015, still a bit up from ASO (2.2). An anomaly of 2.4 would be a record, but the official determination will depend on the SST data set being used by CPC. There is some sensitivity to the particular data sets used.
The CA method, acting on global SON2015 seasonal means as latest input, but using a string of global SST going back one year, has all of its members, staying >1.0 for Nino34 from now thru FMA2016. There is a significant cool down predicted in 2016, ensemble mean -1.10 by fall 2016.
Weights were stable from last month. There are 4 (5) large +ve (-ve) weights in excess of abs(0.10). Of the historically strong warm event years (57, 72, 82, 97) the weights are 0.06, 0.05, 0.07 and 0.22 respectively. Only the weight for 1997 is high.
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 OND2014 thru SON2015). Years in the table are labeled by the year of the middle month of the most recent predictor season. Weights for 1956 and 2014 are less (by 50%) because only half the members use these years ("early" members use 1956, "late" members 2014). Data currently thru Nov 2015.
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Wgt |
Year |
IP |
Weigt |
1956 |
xx |
-6 |
1966 |
Xx |
-9 |
1976 |
Xx |
3 |
1986 |
xx |
1 |
1996 |
xx |
-2 |
2006 |
xx |
2 |
1957 |
xx |
6 |
1967 |
Xx |
8 |
1977 |
Xx |
3 |
1987 |
xx |
4 |
1997 |
xx |
22 |
2007 |
xx |
-3 |
1958 |
xx |
8 |
1968 |
Xx |
4 |
1978 |
Xx |
-4 |
1988 |
xx |
-10 |
1998 |
xx |
0 |
2008 |
xx |
-1 |
1959 |
xx |
19 |
1969 |
Xx |
0 |
1979 |
Xx |
0 |
1989 |
xx |
-3 |
1999 |
xx |
-13 |
2009 |
xx |
7 |
1960 |
xx |
-2 |
1970 |
Xx |
-3 |
1980 |
Xx |
-7 |
1990 |
xx |
-2 |
2000 |
xx |
-9 |
2010 |
xx |
2 |
1961 |
xx |
-2 |
1971 |
Xx |
-8 |
1981 |
Xx |
-7 |
1991 |
xx |
0 |
2001 |
xx |
3 |
2011 |
xx |
5 |
1962 |
xx |
1 |
1972 |
Xx |
5 |
1982 |
Xx |
7 |
1992 |
xx |
1 |
2002 |
xx |
7 |
2012 |
xx |
3 |
1963 |
xx |
9 |
1973 |
Xx |
-12 |
1983 |
xx |
5 |
1993 |
xx |
-8 |
2003 |
xx |
6 |
2013 |
xx |
14 |
1964 |
xx |
-14 |
1974 |
Xx |
-3 |
1984 |
Xx |
-12 |
1994 |
xx |
5 |
2004 |
xx |
3 |
2014 |
xx |
19 |
1965 |
xx |
-9 |
1975 |
Xx |
-7 |
1985 |
Xx |
3 |
1995 |
xx |
-3 |
2005 |
xx |
-6 |
2015 |
xx |
NA |
Weights are high +ve (>+0.10) for 2014, 2013,1997,1959
Weights are high -ve (< - 0.10) for 1999,1988,1984,1973,1964
Ens ave Nino34 anomaly forecasts, for leads -3, -2, -1, 0 etc: in plain numbers (ensemble mean):
2.44 |
2.52 |
2.68 |
2.54 |
2.06 |
1.48 |
1 |
0.5 |
0.13 |
-0.2 |
-0.29 |
-0.38 |
-0.43 |
-1 |
-1.08 |
-1.03 |
-0.85 |
-0.58 |
-0.33 |
-0.22 |
-0.17 |
SON15 |
NDJ |
JFM16 |
MAM |
MJJ |
JAS |
SON |
NDJ16 |
JFM17 |
MAM |
MJJ |
One month ago:
2.2 |
2.26 |
2.6 |
2.96 |
2.73 |
2.27 |
1.66 |
1.12 |
0.56 |
0.13 |
-0.26 |
-0.37 |
-0.46 |
-0.86 |
-1 |
-1.09 |
-1.03 |
-0.87 |
-0.61 |
-0.39 |
-0.31 |
SON15 |
NDJ |
JFM16 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM |
MAM |
Two months ago
1.89 |
1.89 |
2.14 |
2.7 |
2.91 |
2.76 |
2.35 |
1.77 |
1.23 |
0.65 |
0.16 |
-0.27 |
-0.41 |
-0.78 |
-0.82 |
-0.89 |
-0.93 |
-0.86 |
-0.72 |
-0.49 |
-0.3 |
JAS |
SON15 |
NDJ |
JFM16 |
MAM |
MJJ |
JAS16 |
SON |
NDJ |
JFM17 |
MAM |
Three months ago:
1.65 |
1.62 |
1.77 |
2.25 |
2.7 |
2.91 |
2.77 |
2.36 |
1.79 |
1.26 |
0.7 |
0.24 |
-0.15 |
-0.58 |
-0.67 |
-0.69 |
-0.74 |
-0.76 |
-0.69 |
-0.59 |
-0.39 |
JAS |
SON |
NDJ |
JFM2016 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM2017 |
Four months ago
1.21 |
1.19 |
1.23 |
1.48 |
1.89 |
2.32 |
2.5 |
2.39 |
2.06 |
1.62 |
1.22 |
0.76 |
0.32 |
-0.31 |
-0.47 |
-0.53 |
-0.54 |
-0.57 |
-0.57 |
-0.51 |
-0.45 |
MJJ |
JAS |
SON15 |
NDJ |
JFM16 |
MAM |
MJJ |
JAS |
SON |
NDJ |
JFM17 |
Anomalies relative to 1981-2010 climo.