November ENSO Regional Data

[donsutherland1]

The ENSO regional data for November 2004 is now in. The temperatures for each region were as follows:

Region 1+2: 21.89 +0.24
Region 3.4: 27.29 +0.77
Region 3: 25.45 +0.49
Region 4: 29.59 +1.23

Note: All figures are in degrees centigrade

For November, the regional SSTs are closest to those of November 2003. Over the past four months, 2004's SSTs are most similar to those in four previous years: 1977, 1994, 2002, and 2003:

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Year   Avg. Difference
2003   0.253
1994   0.284
1977   0.339
2002   0.381


Overall, the following are the SSTs from each of the ENSO Regions for those years and 2004:

Region 1+2:

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Month/Yr.   1977   1994   2002   2003   2004
August         20.28   19.70   19.94   20.14   19.62
Sept.           19.85   20.16   19.89   20.00   20.07
October       20.98   21.53   21.16   20.99   20.92
November   21.65   22.41   22.25   21.92   21.89


Region 3.4:

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Month/Yr.   1977   1994   2002   2003   2004
August        26.85   27.35   27.79   26.85   27.54
Sept.           26.96   27.00   27.83   26.96   27.47
October       27.30   27.49   28.05   27.19   27.38
November   27.29   27.87   28.27   27.05   27.29


Region 3:

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Month/Yr.   1977   1994   2002   2003   2004
August        24.70   24.81   25.47   25.04   25.05
Sept.           25.26   25.53   25.54   24.97   25.17
October       25.36   25.53   25.85   25.33   25.32
November   25.34   25.87   26.37   25.40   25.45


Region 4:

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Month/Yr.   1977   1994   2002   2003   2004
August        28.73   29.46   29.40   29.05   29.31
Sept.           28.95   29.23   29.44   29.02   29.60
October       28.88   29.45   29.56   29.22   29.55
November   29.11   29.63   29.83   29.31   29.59


Taking this a step further with the idea that these similarities will continue through a good part of the winter, here are the averages for seasonal snowfall (in inches) that resulted under the following criteria employed against the backdrop of similar ENSO profiles and the average for all seasons from 1950-51 through 2003-04 when such criteria were regularly reported:

Average Seasonal Snowfall (1950-51 through 2003-04):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
42.6   95.9   81.0   41.4   24.4   21.5   16.6


Average Seasonal Snowfall (1977-78, 1994-95, 2002-03, 2003-04):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
52.6   110.3   84.4   40.0   38.6   32.2   21.4


December-March QBO Average: -6 to +6:

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
65.1   122.2   92.4   45.2   47.5   39.7   25.2


December-March QBO Average: Above +6 or Below -6:

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
14.9   74.6   60.5   24.1   11.8   9.8   10.1


PDO > 0 (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
65.1   122.2   92.4   45.2   47.5   39.7   25.2


PDO < 0 (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
14.9   74.6   60.5   24.1   11.8   9.8   10.1


NAO < 0 (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
78.0   132.8   91.2   55.5   50.0   50.6   31.6


NAO > 0 (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
27.2   87.8   77.6   24.5   27.2   13.8   11.3


Region 1+2 Avg. Temperature < 25°C (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
65.1   122.2   92.4   45.2   47.5   39.7   25.2


Region 1+2 Avg. Temperature 25°C or Above (December-March):

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
14.9   74.6   60.5   24.1   11.8   9.8   10.1


Rapid Buildup of Fall North American Snowcover:

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
55.2   106.1   88.9   26.7   46.0   32.1   26.4


Slow Buildup of Fall North American Snowcover:

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Boston   Buffalo   BTV   Chi   NYC   Philly   Wash.
50.0   114.5   80.0   53.2   31.3   32.4   16.4


Note: No PNA scenario was included, as all four seasons saw the PNA average > 0.

FWIW, I believe that the following is likely to hold true this coming winter:

• NAO < 0 (still awaiting November data to confirm this)
• Region 1+2 Avg. Temperature: < 25°C
• QBO: Avg. will fall below +6 but above -6
• PDO: Uncertain (awaiting November data)

In addition, the North American snowcover experienced a rapid buildup through October.

Finally, I would caution against using the averages. There is significant variation and appropriate analog years offer greater clarity. These scenarios just some possible outcomes that have occurred in the past. Which one is more applicable to this season, that's a choice one needs to make after reviewing much additional data.