The insurance industry has spent years preparing for more extreme weather. What it has spent far less time preparing for is how quickly weather extremes are beginning to arrive.
Within 10 days this spring, western Europe moved from unusually cool conditions to an intense heatwave, a temperature swing of more than 12°C that left little time for people, businesses or infrastructure to adapt. Scientists have begun describing these abrupt shifts as "temperature whiplash", a phenomenon that challenges traditional assumptions about how climate risk develops and how insurance responds.
The timing is notable. On June 10, the Japan Meteorological Agency declared that El Niño conditions had emerged in the Pacific, while forecasters have warned the event could strengthen significantly over the next year. The issue is not simply whether a Super El Niño materialises, it is whether a more volatile climate is exposing gaps in models and products built around historical patterns of risk.
The EU's Copernicus climate service deployed the term carefully this month. May 2026 was the second warmest May on record globally. More significant, however, was the speed of change. Western Europe moved from a cold spell to an intense heatwave in just ten days, giving crops, ecosystems and businesses little opportunity to adapt.
Spain recorded its highest number of heat-related deaths for May since monitoring began. The insurance industry has models for heatwaves and cold snaps. What it is less accustomed to modelling is the increasingly abrupt transition between them.
Samantha Burgess, strategic lead for climate at the European Centre for Medium-Range Weather Forecasts, said the episode demonstrated "how quickly climate extremes are becoming the new normal rather than the exception".
The implication extends beyond a single weather event. This is not simply a volatile season. It is evidence of a changing baseline.
Against that backdrop, El Niño's return carries significant implications for global risk. The climate pattern, which influences weather systems worldwide, is forecast to strengthen through 2027.
The US Climate Prediction Center has assessed a 67% probability that the current event could evolve into what is being informally described as a "Super El Niño" by 2027. Its effects are unlikely to be uniform. El Niño typically raises drought and wildfire risk across parts of Australia and Asia while increasing flood exposure in parts of the Americas and East Africa. Warmer ocean temperatures can also intensify typhoon activity across the Pacific.
The Atlantic, however, presents a more complicated picture. El Niño conditions generally suppress hurricane activity through increased wind shear, making it harder for storms to develop and maintain structure. Current forecasts project around 13 named Atlantic storms in 2026, including six hurricanes and two major hurricanes.
"El Niño conditions tend to suppress Atlantic hurricane activity due to increased wind shear," said Jeff Waters, product manager at Moody's Insurance Solutions.
"Despite a potentially quieter season, it's important to note that there are other factors that can influence Atlantic hurricane activity throughout the season," Waters said. "It only takes one landfalling storm to cause material impacts to the re/insurance industry."
Rising inflation, post-event demand for labour and materials, and higher rebuilding costs mean insured losses can escalate sharply even when event frequency declines.
For decades, catastrophe underwriting has largely revolved around probability. How often does a flood occur? How frequently does a hurricane make landfall? How likely is a drought in a given region?
Climate whiplash introduces a different challenge. The issue is no longer simply frequency, but velocity: how rapidly conditions move from one extreme to another and whether existing coverages are designed to respond.
If climate whiplash becomes a persistent feature of the risk landscape, insurers may eventually need products designed around sequences of events rather than individual catastrophes.
Kevin Dedieu, chief scientific officer and co-founder of Descartes Underwriting, argued that parametric insurance may be better suited to some emerging climate risks.
"Conventional policies simply respond to damage," he said. "In general, parametric uses a more precise definition of an event to trigger coverage. It would be possible to construct 'whiplash' coverage triggered when sustained heat is followed by severe rainfall, for example."
Such products have not yet been deployed, according to Dedieu. However, parametric cover linked to extreme heat, rainfall or flood levels already exists in parts of the market. Claims can be triggered by objective thresholds such as temperature, rainfall accumulation or water depth rather than physical damage alone.
Whether a Super El Niño ultimately shifts capital away from traditional catastrophe lines remains uncertain.
"The peak is still uncertain, and no major event has happened yet, so capacity remains unaffected," Dedieu said. "A super El Niño would increase the probability of certain extreme events occurring, but other local factors would have to come into play for one to materialise."
His assessment was measured. Market-wide consequences would likely require a major event in a highly exposed region such as the United States, Europe or Japan.
The economic stakes are significant. Research from Dartmouth College estimated the 1997-98 El Niño reduced global GDP by $5.7 trillion over five years, while Swiss Re projects insured catastrophe losses could reach $148 billion in 2026 if long-term trends hold.
Waters' warning that a single landfalling hurricane can still reshape a market remains true. But the broader lesson from Europe, and from the emerging El Niño cycle, may be that catastrophe risk is becoming less about the number of events and more about the speed at which conditions deteriorate.
The insurance industry has become increasingly sophisticated at modelling frequency. The next challenge may be modelling volatility itself.
