Following a March report announcing the arrival of a weak and elusive El Niño/Southern Oscillation (ENSO), on May 14 the NOAA National Weather Service Climate Prediction Center issued an updated forecast. NOAA’s latest analysis indicates a 90% chance that El Niño will continue through the summer and an 80% chance that it will remain through the rest of 2015. NOAA has increased the confidence in its forecast over the last two months, based on observations of increasing sea surface temperatures and other atmospheric changes.
However, what the El Niño forecast means for precipitation along the western part of the U.S. is still “too early to forecast with much confidence,” in part because the effects of El Niño on temperature and precipitation in the United States aren’t generally experienced until the colder months of the year (October-March).
NOAA’s El Niño portal provides updates, discussions and blogs about the developing atmospheric event. NOAA also updates the ENSO Diagnostic Discussion on the second Thursday of each month.