Guy Carpenter is projecting a less active 2026 Atlantic hurricane season, pointing to a strengthening El Niño that is expected to suppress storm formation across the basin during the peak months.
The firm's May 2026 North America Peril Advisory placed the probability of El Niño conditions at 90% during the August-to-October peak, citing data from the National Oceanic and Atmospheric Administration's Climate Prediction Center.
"El Niño typically increases wind shear across the tropical Atlantic, disrupting tropical cyclone development," the advisory said, framing the climate phase as the dominant suppressor for the upcoming hurricane season.
Guy Carpenter has separately noted that each El Niño cycle carries a distinct regional signature, with cyclone tracks shaped by sea surface temperatures, trade winds and atmospheric circulation. Flood and wildfire exposures shift along with those patterns, particularly across Australia and Indonesia, which have historically faced suppressed rainfall and faster fuel drying during the phase.
The broker pointed to past analogs including the 1997-98 floods in California and Peru, as well as drought-driven wildfires in Indonesia in 1997-98 and 2015-16. Carriers, it said, should treat the cycle as a portfolio-reshaping event and reassess geographic concentrations and peak peril assumptions.
The chances of a "Super El Niño" — defined as warming of more than 2°C above normal in the Pacific's Niño 3.4 region — were also rising, although peak intensity was expected to arrive after the hurricane season ended.
Records dating to 1950 show that activity under Super El Niño conditions has averaged about 10 named storms and four hurricanes. The standout exception was 2023, when record-warm Atlantic sea surface temperatures produced 20 tropical storms, seven hurricanes and three major hurricanes.
Sea surface temperatures remained above average across the Gulf of Mexico and the subtropical Atlantic, which may partly offset the suppressive effects of stronger wind shear.
The main development region, however, was running slightly cooler than in recent years, with drier-than-normal conditions also expected there and across the Caribbean Sea during the peak of the hurricane season.
Colorado State University's April 9, 2026 outlook aligned with the slightly below-average view, projecting 13 named storms, six hurricanes, two major hurricanes and an Accumulated Cyclone Energy index of 90. The 1991-2020 baselines stand at 14 named storms, seven hurricanes, three major hurricanes and an ACE of 123.
CSU identified 2006, 2009, 2015 and 2023 as analog years, assigning below-average odds to major hurricane landfalls along the continental US coastline and across the Caribbean.
Guy Carpenter cautioned, however, that seasonal storm tallies were a poor predictor of insured losses. Between 1950 and 2025, annual hurricane counts ranged from two to 15, while insured losses spanned from marginal to more than $100 billion, with the landfall-to-basin ratio varying between 0% and 86% and averaging 20% to 25%.
"Insured losses are driven by hurricane landfalls, affected population centers and the characteristics of impacted structures — not by basin activity alone," the broker said, a distinction it described as critical for reinsurers and cedents weighing exposure ahead of the June 1 start of the hurricane season.
The advisory was produced by Guy Carpenter, a Marsh business, drawing on data from NOAA, the National Hurricane Center, Colorado State University and the University of Maine's Climate Reanalyzer.
