Suddenly, an immense Kelvin Wave has emerged just east of the Dateline in the equatorial Pacific Ocean likely to shift eastward during the next several weeks and accelerate upper ocean heat to fuel El Nino onset. The rate of expected warming is similar with the strongest El Nino’s on record in 2015 and 1997. Analogs and dynamic models are supportive of a potential record strength El Nino in 2026.

Last week, the Nino4 SSTA warmed too above the El Nino threshold. The Nino4 region is located on either side of the Dateline and the warming in this region is a southwestward expansion of surface warming associated with an intense marine heatwave off the West Coast of North America.

Although remaining within the ENSO prediction barrier (EPB) strongest during MAR/APR, most dynamic models are projecting a moderate-to-strong El Nino to emerge mid-to-late 2026. Coinciding with the strong El Nino, is a projection of positive phase Indian Ocean dipole.

During the past 30 days, 2-meter temperature forecasts verification skill scores (using anomaly correlation) reveal best skill is across South America trailed by a tie between North America and Europe with Australia in last place.