El Niño/La Niña Update (May 2024)

The 2023/24 El Niño event is ending. Since its peak during boreal winter, sea surface temperature anomalies in the equatorial Pacific have steadily weakened. The latest forecasts from WMO Global Producing Centres of Long-Range Forecasts give equal chances (50%) of ENSO-neutral conditions or a transition to La Niña during June-August 2024. Slightly later during July-September, La Niña conditions are more likely than not, with around 60% chance, while ENSO-neutral is estimated with around 40% chance. During August-October and September-November of 2024, there is a 70% chance of La Niña prevailing, with a 30% chance of ENSO-neutral conditions. The likelihood of El Niño redeveloping is negligible during this time. Historically, seasonal forecast models at this time of year are known to have relatively low skills, commonly known as the Northern Hemisphere "spring predictability barrier", and therefore these ENSO forecasts should be interpreted with caution. National Meteorological and Hydrological Services (NMHSs) will closely monitor changes in the state of ENSO over the coming months and provide updated outlooks, as needed.