MEI Rises to +0.454

[donsutherland1]

The June-July period saw the Multivariate ENSO Index increase to 0.454 after it had dipped to 0.286 for the May-June period. At this time, it continues to remain very close to levels achieved in 1979.


Year..........AM............MJ............JJ
1979.........0.431........0.467........0.360
2004.........0.428........0.286........0.454

Consequently, this similarity continues to support model forecasts for the development of at least a weak El Niño during the winter, likely in the October-November-December period.

[NWIASpotter]

Is it possible you can explain this a little more?? I know I'm not completely familiar with it. And I'm sure that a lot of other people don't have a clue at what this means.

[donsutherland1]

NWIASpotter,

The computer guidance has been suggesting for some time that a weak El Niño is likely to set in during the coming winter.

<img src="http://iri.columbia.edu/climate/ENSO/currentinfo/SST_table.gif">

The latest reading of the Multivariate ENSO Index (one broad indicator of ENSO) has continued to remain very close to its levels of 1979. This reality provides some support to the modeled ideas, as 1979 saw a weak El Niño set in for the winter. In other words, the actual data argues for greater confidence in the modeled ideas than might otherwise be the case, especially during a cool PDO phase (El Niños tend to be weaker and less frequent during the cool PDO phase).

In addition, the idea that no El Niño is likely until most or all of the 2004 hurricane season has passed, suggests that an active season should be likely (given additional factors that point in that direction). While the rising El Niño might tend to suppress tropical activity somewhat toward the end of the season, things still look good for an active season overall.

[NWIASpotter]

Thanks Don Sutherland, it was appreciated