Accelerating El Nino Intensity Slows Down

Climate Impact Company ENSO Climate Diagnostics

Issued: Monday August 24, 2026

Highlight: Accelerating El Nino intensity slows down.

Fig. 1: The equatorial Pacific Ocean subsurface temperature anomalies.

Discussion: Climate Impact Company refers to El Nino intensity as “strong” to “super” intensity due to relative Nino34 SSTA stuck at +1.8C and conventional Nino34 SSTA just above the +2.5C super El Nino threshold (Fig. 1). However, without question, due to immense subsurface heating in the equatorial East Pacific (Fig. 2), potential for the strongest El Nino on record later this year remains indicated. The daily southern oscillation index (SOI) has sufficiently fluctuated in recent weeks to cause the 30-day SOI average to ease slightly below the super El Nino threshold (Fig. 3). The 2-week SOI forecast favors weak positive phase suggesting the slowdown in El Nino intensity will continue.

Fig. 2: Upper ocean is immense east of the Dateline in the eastern equatorial Pacific Ocean.

Fig. 3: The daily southern oscillation index for the past 30 days.