A transition from El Niño–Southern Oscillation (ENSO)-neutral is expected in the next couple of months, with a greater than 90% chance of El Niño persisting into the Northern Hemisphere winter. El Niño is likely to form during the May-July season and persist into the winter. The combination of a forecasted third westerly wind event in mid-late May, and high levels of above-average oceanic heat content, means that a potentially significant El Niño is on the horizon. While at least a weak El Niño is likely, the range of possibilities at the end of the year (November-January) includes an 80% chance of at least a moderate El Niño to a ~55% chance of a strong El Niño. It is still possible the tropical atmosphere does not couple with the ocean, and El Niño fails to materialize (5-10% chance). In summary, a transition from ENSO-neutral is expected in the next couple of months, with a greater than 90% chance of El Niño persisting into the Northern Hemisphere winter. This discussion is a ...