El Niño ‘Supersized Before Our Eyes’: What This Means For Winter In CT

El Niño is “being supersized before our eyes,” and the strengthening climate pattern could bring extreme conditions to Connecticut this winter, according to the latest forecasts for what could become a historically strong event.

The World Meteorological Organization said Sept. 3 that El Niño is firmly established and expected to intensify into a very strong event before peaking near the end of 2026. The U.N. agency said the effects on rainfall, drought, flooding and extreme heat could continue well into 2027.

“The science leaves no room for doubt: the planet is in uncharted waters, and those waters are heating up,” U.N. Secretary-General António Guterres said of the supersized El Niño in a news release. “The world is in the danger zone of extreme weather.”

For residents of Connecticut, that could mean a warmer and wetter than normal winter, according to the 2026-27 winter outlook from the National Oceanic and Atmospheric Administration.

El Niño is a periodic warming of the central and eastern tropical Pacific Ocean that changes atmospheric circulation and shifts weather patterns around the world. In the United States, its effects are generally most pronounced during winter.

NOAA’s Climate Prediction Center confirmed in an update Thursday that El Niño strengthened further in August and has a greater than 90 percent chance of becoming very strong this fall and winter.

The agency also raised the chance of a historic event from 69 percent in August to 75 percent. In this case, “historic” means the three-month strength index would exceed previous El Niño events in NOAA’s record dating to 1950.

The Pacific Ocean continued to heat up in August, adding more fuel to El Niño. In the region scientists use to measure it, water temperatures were about 3.2 degrees Fahrenheit above normal, compared with 2.5 degrees in July. Farther east, they were about 6 degrees above normal. That extra heat can shift the jet stream and increase the odds of a wetter winter across the southern United States and a warmer, drier one across much of the northern tier.

A stronger El Niño increases the odds that its familiar weather patterns will develop, but NOAA cautioned that those effects are not guaranteed in every region or community. Seasonal outlooks show whether an area has elevated odds of above-, below- or near-normal conditions. They do not predict individual snowstorms, floods, cold snaps or atmospheric rivers months in advance.

Nationally, NOAA’s latest long-range outlook favors wetter conditions across much of the southern United States, from California and the Southwest through the southern Plains, Gulf Coast and Southeast, with wetter conditions eventually extending along much of the East Coast. Warmer and generally drier conditions are favored across much of the northern tier, including the northern Plains, northern Rockies, Great Lakes and inland Pacific Northwest. The Ohio and Tennessee valleys have no clear precipitation signal, while much of Alaska is expected to be warmer, with drier conditions developing across the mainland.

In Connecticut and the rest of the Northeast, the region leans slightly drier than normal this fall overall, although short-term patterns may produce wetter periods. Warmer-than-normal conditions are favored this winter, while coastal areas increasingly lean wetter.

A wetter winter does not necessarily mean a snowier one. Whether precipitation falls as rain, snow or ice depends on temperatures when individual storms arrive. Likewise, a warmer seasonal forecast does not rule out periods of bitter cold or major winter storms.

NOAA is scheduled to release updated winter temperature and precipitation outlooks Sept. 17.