The equatorial waters of the Eastern Pacific off the coast of South America have steadily warmed during March, and it appears increasingly likely that the current La Niña event will be over by June. This week, sea surface temperatures (SSTs) over the tropical Eastern Pacific in the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region", warmed to 0.8°C below average, according to NOAA. This puts the current La Niña in the "weak" category for the first time since the event began in July 2010. If these SSTs continue to warm such that they are no more than 0.5°C below average, the La Niña event will be over, and we will be in "neutral" conditions. An animation of SSTs since late November shows this developing warmth nicely. Springtime is the most common time for a La Niña event to end; since 1950, half of all La Niñas ended in March, April, or May. The weakness displayed by the current La Niña event has prompted NOAA's Climate Prediction Center to predict that La Niña will be gone by June. As La Niña continues to wane, we can expect that rainfall over the drought regions of the southern U.S. will gradually return to normal levels by mid-summer.
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Of the six analogue years since 1950 when La Niña ended in spring, only 1996 had a much above average February SST anomaly in the MDR (0.61°C.) Thus, I believe it is a reasonable speculation at this point to predict this year's hurricane season will be similar to 1996, with its 13 named storms, 9 hurricanes, and 6 intense hurricanes--assuming we end up with neutral and not El Niño conditions this fall.
http://www.wunderground.com/blog/JeffMasters/article.html
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