NOAA’s September Outlook Offers a First Look at the Strong El Niño Winter to Come

NOAA recently released its official forecast for September in the United States. The agency reports that El Niño — a recurring climate phenomenon in which unusually warm ocean temperatures in the South Pacific drive shifts in weather patterns worldwide — is strengthening fast.

Ocean temperatures have warmed to 3 degrees Celsius (5.4 Fahrenheit) above average in localized regions of the Pacific, pushing the Niño 3.4 Sea Surface Temperature index (SST) to 1.8 C above normal. This marks at least a 0.3 C jump from the beginning of summer, and other agencies, such as the IRI, report a current index value as high as 2.7 C.

For a year to be classified as an “El Niño” year, the index must reach at least 0.5 C above normal. A strong El Niño reaches 1.5 C or higher, meaning the current 1.8 C reading already puts the event squarely in “strong” El Niño territory — and possibly trending toward a “very strong” El Niño year, defined as greater than 2 C.

El Niño conditions are expected to persist for months to come, and even strengthen as the 2026-2027 winter approaches. NOAA currently predicts, with 97% confidence, that El Niño conditions will continue at least through spring 2027. Furthermore, there is an 81-90% chance the event becomes “very strong” (greater than 2 C) by its expected peak between October 2026 and January 2027.

• Related: The 2026-27 El Niño Ski Season Could Be the Biggest in Decades

Looking at winter temperature and precipitation data from the last four strong El Niño years — all occurring since 1957 — much of the United States has historically seen both above-average winter temperatures and precipitation. The northern part of the country has typically seen the most noticeable warming, as regions such as the Great Plains, Northern Rockies, and Pacific Northwest have recorded above-average winter temperatures during each of the last four strong El Niño winters (although warming in the latter two regions was typically less dramatic).

For the southern and eastern regions of the country, a strong El Niño winter delivers more of a mixed bag in terms of anomalous temperatures. The Southwest has consistently seen average or even cooler-than-normal winter temperatures during the last four strong El Niño years, while the Southeast has also seen very little in the way of warming. The Mid-Atlantic and Northeast can typically expect slightly above-average winter temperatures; however, the 1957-58 El Niño actually brought cooler weather to the region.

• Related: El Niño 2026-27 Ski Forecast August Update: 90%+ Odds, a Historic Threshold, and California’s Best Setup in Years

As for winter precipitation, the last four strong El Niño winters have brought above-average precipitation to the Pacific Northwest. The entire eastern seaboard also typically sees more winter rain than usual, though this pattern is more variable, as some strong El Niño winters have brought drier seasons to these areas instead. The Southwest, Great Plains, and Rockies should all expect near-average precipitation throughout a strong El Niño winter.

The September outlook, released Aug. 20, largely follows the trends typical of a strong El Niño year, with a few notable exceptions. Warmer-than-average temperatures are expected throughout much of the country, particularly in the Southeast, Central Rockies, Pacific Northwest, and Southeast Alaska. However, the Northern Plains and Great Lakes region, which can see dramatic warming during strong El Niño years, is expected to see near-average temperatures during September.

Precipitation-wise, accumulation is actually expected to be above average in the Southwest, Southern and Central Rockies, and Southern Appalachia. Meanwhile, the Pacific Northwest — a region that typically receives above-average precipitation during a strong El Niño — in contrast to trends from prior years, is actually expected to see a decline in accumulation this September.

Unfortunately, the September outlook doesn’t look particularly promising in the way of early-season, powder-fever-inducing snowfall. If a cold front hits at the right time, snow could perhaps be seen in regions such as the Southern Rockies or the Front Range of Colorado, given the high expected precipitation. However, as previously stated, temperatures in these areas are forecast to be on the higher side, so early-season enthusiasts looking to bust out the rock skis probably shouldn’t hold their breath.

As with any winter, a strong El Niño pattern brings a lot of uncertainty and varied conditions across the many ski regions of the U.S. However, knowledge of previous winters that also experienced strong El Niños can be useful in predicting what may be to come this year. While skiers and riders may be eager for concrete answers, especially on the heels of what was largely a disappointing past winter, the fact of the matter is that we’re still a long way out from having a clear view of what’s in store for the winter of 2026-27.