ENSO events are notoriously hard to forecast.
Earlier this year, it really appeared that an El Nino event would occur, forming in northern hemisphere autumn. It looked like, from the available heat in the tropical Pacific's waters, that this event would be spectacular, rivaling if not exceeding the 1997 El Nino event. For the parched western US, this would have been welcome despite the disruption it'd bring. It'd essentially start raining in late December and not really stop until March.
When the first preliminary forecasts were released earlier this year, I just didn't see it. I just didn't see the super-El Nino happening. As data came in and as I kept watch over the summer, the conditions necessary just did not come together.
And now, it looks likely that this will not occur.
Long-term weather forecasters say it is now unlikely that a strong El Niño will develop this fall, dimming hopes in California for heavy rains that might bring relief from a severe drought.
In its latest monthly forecast, the federal Climate Prediction Center in College Park, Md., said that while there was still about a two in three chance that El Niño would develop, perhaps in the next two months, it would most likely be weak.
Earlier this year, some scientists had said that rising water temperatures and changing wind conditions in the Pacific suggested that a major El Niño event, perhaps as strong as the one of 1997-1998, was possible. That winter was one of California’s wettest on record, with widespread flooding and frequent mudslides.
“Certainly expectations have declined from what folks were saying earlier in the year,” said Mike Halpert, acting director of the center, which is part of the National Oceanic and Atmospheric Administration.
For California, this is possibly not good news. Not good news at all. California may still see above-average rain this winter, but they won't dent the drought.
El Ninos are highly disruptive elsewhere in the world. NOAA has an excellent primer on the subject.