Overview
- The U.S. Climate Prediction Center on Sept. 10 raised the chance that October–December sea-surface anomalies will reach a historic RONI value to 75% and kept greater than 90% odds that the event will be very strong through fall and winter.
- Ocean measurements show unusually large heat: monthly sea-surface anomalies in parts of the tropical Pacific exceeded +3°C and widespread subsurface warm pools topped +10°C, conditions that can sustain or strengthen El Niño over months.
- The strengthened El Niño has suppressed Atlantic hurricane formation so far this season, leaving the basin unusually quiet at the climatological peak and making a record-late first Atlantic hurricane this year possible if none forms soon.
- By contrast, the eastern and central Pacific have been hyperactive with many named storms and hurricanes that have affected Hawaii and driven high surf along the U.S. West Coast, and record-warm Gulf and Florida waters raise a separate late-season risk to the Southeast if a storm finds a favorable window.
- Humanitarian and economic effects are already reported, with drought-driven crop losses in Central America, upward pressure on staple prices, and warnings from aid and weather agencies that impacts could intensify through late 2026 and into early 2027.