Figure 2. The deadliest U.S. weather disaster of March 2014 was the tragic landslide at Oso, Washington that killed 41 people and did $10 million in damage. The landslide was triggered by record March rains that saturated the soils. The nearby Seattle airport measured 9.44” (240 mm) of precipitation in March, a new record for the month. Photo by Washington State Patrol.
March 2014 featured neutral El Niño conditions in the equatorial Eastern Pacific, but NOAA has issued an El Niño Watch for the summer and fall of 2014, giving a greater than 50% chance that an El Niño event will occur by the summer. The April 10 El Niño discussion from NOAA's Climate Prediction Center noted that "there remains considerable uncertainty as to when El Niño will develop and how strong it may become. This uncertainty is amplified by the inherently lower forecast skill of the models for forecasts made in the spring." None of the El Niño models (updated in mid-April 2014) predict La Niña conditions for peak hurricane season, August-September-October 2014, and 16 of 20 predict El Niño conditions.
Temperatures in the equatorial Eastern Pacific need to be 0.5°C above average or warmer for three consecutive months for an El Niño episode to be declared; sea surface temperatures were +0.2°C from average as of April 21. El Niño conditions tend to make quieter than average Atlantic hurricane seasons, due to an increase in upper-level winds that create strong wind shear over the Tropical Atlantic. There is currently a Westerly Wind Burst (WWB) over the equatorial Pacific Ocean that is helping push warm water eastwards towards South America. If this Westerly Wind Burst persists and expands eastwards through early May, the odds of an El Niño event will increase.
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2669
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