A 3.05°C Pacific record is a January renewal problem

Sea surface temperatures at the heart of the 2026-27 El Niño reached 3.05 degrees Celsius above the 1991-2020 average, eclipsing the 3.02 degrees set in late November 2015 and the highest level since modern records began, according to the Guardian, which first reported the new high. The event has not peaked, and climate scientist Zeke Hausfather forecasts 4.0 degrees above average for November and December, a level he called "mind-blowing."

The institutions have stopped hedging. The UK Met Office forecasts the largest such event since the 19th century; the World Meteorological Organization puts it as the largest in at least 1,000 years. NOAA assigns a 90% or greater probability that a very strong El Niño persists from September 2026 through January 2027, and the WMO's September advisory carried what it called an "exceptionally high likelihood of nearly 100%" of persistence through February 2027, language the organization itself described as "unequivocal."

The Atlantic wind market has not hardened. Swiss Re's September sigma explains why: a strengthening El Niño may temper North Atlantic hurricane activity in the second half of the year, even as the report warned that "the risk of a costly major event remains." The same publication put global insured natural catastrophe losses in the first half of 2026 at an estimated $42 billion. Against that loss record, damage appears to have relocated rather than removed — hurricanes in Hawaii, floods across the United States, record heat domes worldwide, deadly storms in Chile and temperature records in Peru, per the Washington Post's tracking, with August 2026 the hottest month ever recorded at global surface level, 1.65 degrees Celsius above pre-industrial levels, on Copernicus data.

January is where this lands. Hausfather's historical comparison is that the very strong events of 1997-98 and 2015-16 were associated with hundreds of billions of dollars in damages globally, and that this one is "leaving those past ones in the dust." Insurance Business America's report argues the loss potential presents a hazard that cat models calibrated on weaker historical events may underestimate. For cedents and ILS funds, the renewal likely features Atlantic wind capacity that again looks ample while the arguing happens over aggregate covers, per-occurrence retentions and secondary-peril sublimits.

As this publication has argued, a $1.3 trillion surplus turns January into a test of capital discipline rather than loss capacity, and the WMO's persistence forecast puts the warmest-year baseline on the renewal calendar. The 3.05-degree print sharpens both, because the discipline gets tested on terms rather than rate: the losses likely arrive through perils that sit under sublimits and inside aggregates, not through the one peril the market prices most confidently. Watch whether reinsurers hold secondary-peril sublimits through the negotiation, and whether February's persistence call arrives as forecast.