The June 5, 2014 El Niño update from NOAA's Climate Prediction Center gives a 70% chance that El Niño will form this summer, and an 80% by fall, but El Niño odds are higher than this. A strong Madden Julian Oscillation (MJO) event is forecast to develop over the central-eastern Pacific later this month in through early July (the Madden Julian Oscillation (MJO) is a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days.) This MJO location favors for another period of westerly wind bursts over the Central Pacific, an atmospheric signature that is likely to be the final kick needed for a blossoming El Niño event.

As I blogged about on February 21, there has been a noticeable warming in the eastern Pacific over the past few months in response to one of the most impressive downwelling oceanic Kelvin waves observed since satellite measurements began in the late 1970s. Recall that we observed a series of strong westerly wind bursts over the western-central Pacific Ocean this past winter. These westerly wind bursts can be tied to the state of the MJO as well as other equatorial waves and tropical cyclones.

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My thoughts on this summer: Since the atmosphere has NOT yet locked into an “El Niño state”, we might expect the typical cooler-than-average summer conditions that the eastern 2/3 of the U.S. typically experiences during an El Niño event to be delayed. This means we can expect periods of hot weather across the major natural gas and power markets this summer. We do not believe these heat waves will be prolonged in nature, and it is difficult to pin-point the timing and magnitude of such events. But we can expect them to continue until the atmosphere “feels” the El Niño developing beneath in the ocean. With a possible strong MJO event on the horizon, it does suggest however that the atmosphere could lock into an El Niño state sometime between July and August.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2694