As of late June, the status of the tropical Pacific was “ENSO-neutral” – neither one nor the other – according to the National Oceanic and Atmospheric Administration's Climate Prediction Center.
But that's not expected to last much longer. CPC forecasters are calling for a 70 percent chance of El Niño developing sometime this summer and an 80 percent chance of El Niño appearing by fall or winter.
It's unclear at the moment how strong this event is likely to be, notes Anthony Barnston, chief forecaster at the International Research Institute for Climate and Society in New York, a joint project between Columbia University and NOAA. A majority of forecast models suggest that this El Niño will be moderate. In the event this El Niño tips toward weak or strong instead, the models suggest it has a slightly higher likelihood of being weak rather than strong.