As of September 11, the Atlantic has done something it has never done in 76 years of reliable record-keeping: gone the entire climatological peak of hurricane season without producing a single hurricane. The previous latest start belonged to 2002, when Hurricane Gustav did not form until September 11. This year we have matched that mark and, with nothing organized on the horizon, we are about to blow past it.
The number that tells the real story is accumulated cyclone energy, or ACE, the standard measure of a season's combined storm intensity and duration. As of today, Atlantic ACE sits at 4.4 units. The date average is 60.5. That is beyond slow, shattering historical records.
Three named storms have formed, Arthur, Bertha, and Cristobal, all weak systems that spun up in the Gulf or subtropics and never approached hurricane strength. For context, the 1991-2020 average was roughly 4 named storms by this point in the season, and the 2016-2025 average is 6.1. We are running about 51 percent below the recent-decade norm on storm count and 84 percent below average on ACE.
Compare it to other quiet years insurers remember. 2022 produced three or fewer named storms by late August, similar to this year, but still ended with a Category 4 landfall in Florida that cost the industry more than $60 billion. By August 21, 2019, it had only two named storms, and it finished the season with 18, including Dorian. The lesson for anyone pricing risk off a slow start to hurricane season is that a quiet open does not guarantee a quiet close.
The proximate cause is well understood and well forecast. El Niño is the warm phase of the El Niño-Southern Oscillation, a periodic warming of surface waters in the central and eastern tropical Pacific that reorganizes atmospheric circulation worldwide. NOAA currently assigns a 90 percent probability of strong or very strong El Niño conditions during the August-October window, with nearly a coin-flip chance of reaching very strong territory.
For the Atlantic, El Niño's fingerprint is vertical wind shear. Warmer Pacific waters shift the jet stream and strengthen upper-level winds across the Caribbean and the Main Development Region, the stretch of open ocean off West Africa that normally spawns the Atlantic's biggest, longest-track hurricanes. Strong shear tears nascent storms apart before they can organize. Add stronger-than-normal Caribbean trade winds and a West African monsoon pattern that is not feeding moisture where it needs to, and you get a hostile environment for tropical development almost everywhere in the basin except close to the US coast.
The historical pattern here is about as clean as seasonal forecasting gets. Every Atlantic season that has coincided with a strong El Niño since 1950 has finished below normal. Only 1965 came close to a normal year, and that was because Hurricane Betsy alone was long-lived enough to run up the ACE tally.
El Niño years also change where storms go, not just how many form. With the Main Development Region hostile to development, what activity does occur tends to spin up closer to home, in the Gulf of Mexico and the subtropics, exactly where Arthur and Bertha formed this year. The six strong or very strong El Niño seasons since 1950 collectively produced only four US hurricane landfalls, and just one major: Betsy, a Category 4 that crossed South Florida and then hit Louisiana in 1965. That is the number underwriters should actually hold onto. It is not zero, and it is not distributed evenly. A quiet season with one bad Gulf Coast landfall is entirely consistent with the record.
For carriers and reinsurers heading into January 1 renewals, a historically quiet season removes a major source of 2026 loss activity and will show up as favorable in loss ratios and cat bond mark-to-market pricing. That is real, and it will put downward pressure on property CAT rates. It should not change anyone's view of tail risk. Betsy is the reminder that sits inside every strong El Niño season.
El Niño's suppressive effect is not limited to the Atlantic. Rather than eliminating tropical cyclone activity, it tends to redistribute it globally. While increased vertical wind shear typically suppresses Atlantic hurricane development, the Eastern and Central Pacific often become more favorable for tropical cyclone activity. The Central Pacific, including waters near Hawaii, has historically experienced increased activity during moderate-to-strong El Niño years.
Australia presents an important contrast. El Niño does not typically bring more tropical cyclones to Australia. Instead, it is generally associated with fewer tropical cyclones, a later start to the northern wet season, and drier conditions across parts of eastern Australia. Those conditions can also increase the risk of drought and bushfires, particularly across southeastern Australia.
The underlying driver is the broader shift in the tropical Pacific Ocean and atmospheric circulation. During El Niño, warmer water and tropical convection shift eastward, away from Australia, altering the conditions that normally support cyclone development in the Australian region.
For insurers, that means the risk does not simply disappear; it changes form and geography. During El Niño, Australian writers may need to pay closer attention to drought, heat, and bushfire exposure, even as seasonal cyclone frequency tends to decline. During La Niña, the pattern generally reverses, with greater tropical cyclone activity and increased flood risk across Australia.
The net read for insurance professionals: enjoy the quiet Atlantic peak season while it lasts, price the Gulf Coast concentration risk it creates, and watch fire and drought lines in Australia rather than wind. Seasonal patterns are real and forecastable. Individual storms and single seasons still write their own headlines.