Overview
- The World Meteorological Organization said Tuesday there is an about 80% chance El Niño will develop between June and August and roughly a 90% chance conditions will persist into November.
- Observed ocean data show sea-surface warming in the central-eastern equatorial Pacific and unusually hot subsurface reservoirs that exceed seasonal averages by more than 6°C, signals that support the forecast.
- Most international forecast models project at least a moderate El Niño with a subset indicating a possibly strong peak, but the WMO cautioned that model spread and the spring predictability barrier leave peak strength uncertain.
- Regional outlooks anticipate a reshuffle of rainfall and storm activity with wetter-than-normal conditions in parts of the southern United States, southern South America and the Horn of Africa, and drier conditions or weaker monsoon rains in Australia, Central America and parts of South Asia.
- UN and WMO leaders urged early preparedness because higher global temperatures and altered rainfall patterns could raise heat-related illness, strain food and water supplies, and amplify local vulnerabilities such as Philadelphia's ongoing drought that may change how summer heat plays out there.