Winter 2026–27 outlook: What to expect across the US and Europe

Winter 2026–27 is shaping up to be unusually warm across both North America and Europe. But that does not mean cold outbreaks, snowstorms, or other disruptive weather are off the table.

The latest Xweather outlook projects 2,305 Gas-Weighted Heating Degree Days for the North American season. GWHDDs measure the effect of temperature on heating demand, giving greater weight to areas where natural gas consumption is highest. The forecast would make this the sixth-warmest winter since 1950, with approximately 5% fewer GWHDDs than the 10-year normal and 9.5% fewer than the 30-year normal.

The European outlook projects 1,319 Population-Weighted Heating Degree Days, which give greater weight to temperatures in more densely populated areas. That would make winter 2026–27 the 12th warmest in records dating back to 1981, with approximately 3.1% fewer PWHDDs than the 10-year normal and 6.8% fewer than the 30-year normal.

Across North America, above-normal temperatures are expected across most of the United States and Canada. In Europe, the warm signal is strongest across central and southern regions, while temperatures are forecast to remain closer to seasonal norms across Scandinavia and the British Isles.

The seasonal average, however, tells only part of the story.

A potentially historic El Niño is driving the winter outlook

Confidence in both outlooks is higher than usual because three important drivers are aligned: a potentially historic El Niño, unusually warm global oceans, and a broader climate pattern that continues to favor warmth.

US: Strong El Niño analogs point to lower heating demand

Sea surface temperatures in the Niño 3.4 region of the tropical Pacific have already reached record levels for this time of year, and forecast guidance indicates that further strengthening is possible. The event could become one of the strongest observed in the modern record.

Previous strong El Niño winters—including 1997–98, 2015–16, and 2023–24—all ranked among the ten warmest North American winters since 1950. Across the strong El Niño winters analyzed by the Xweather forecasting team, more than 70% of winter days produced below-normal heating demand.

That historical consistency provides a strong foundation for the forecast and helps explain how the coming winter is likely to unfold.

Europe: Warm Pacific and Atlantic waters reinforce the signal

The developing El Niño also plays a significant role in the European outlook. However, given Europe’s proximity to the Atlantic, conditions in that basin are another important contributor.

Atlantic waters remain anomalously warm, with the Atlantic Multidecadal Oscillation measured at +0.8 in August—the second-warmest August value since 1950. Together, the warm Atlantic, strong El Niño, and wider climate trend support above-normal temperatures across much of Europe.

The European analogs tell a similar story. The strong El Niño winters of 1997–98, 2015–16, and 2023–24 averaged 1,269 PWHDDs—lower than the current forecast of 1,319 and the 10- and 30-year normals. Across those winters, 71.9% of days were warmer than normal, indicating that the European outlook could still carry further warm potential.

A warmer winter can still deliver cold extremes

Strong El Niño does not eliminate cold weather. Instead, it tends to change the frequency and persistence of cold periods.

US: Cold periods are likely to be shorter and less frequent

Recent strong El Niño winters averaged approximately 77% warmer-than-normal days and 23% colder-than-normal days. Warm stretches lasted an average of 15 consecutive days, while cold stretches averaged around five.

In practical terms, cold air can still arrive, but it is less likely to dominate the season. Warm periods occur more often and tend to persist for longer.

The reduction in extreme cold risk is also not evenly distributed. Northern markets historically experience a meaningful moderation in their coldest temperatures during strong El Niño winters. In Chicago, for example, the coldest 2% of winter mornings averaged approximately –4°F during strong El Niño winters, compared with –14°F in the broader climatology.

Across parts of the southern United States, the change is much less pronounced. Dallas and Houston show little difference in their coldest temperatures, suggesting that southern regions remain exposed to occasional severe cold even within a broadly warmer pattern.

Europe: Arctic blocking remains the primary cold risk

Across Europe, periodic bouts of colder weather remain possible despite the strong warm signal. Arctic blocking would be the primary reason for colder-than-forecast conditions, even if such an event proved relatively brief.

Winter 2009–10 demonstrates what can happen when Arctic blocking overrides the broader El Niño signal. Despite being an El Niño winter, it ranked as the fourth coldest European winter since 1981, with 1,591 PWHDDs.

A repeat is considered less likely than the prevailing warm scenario, but it illustrates why significant cold cannot be ruled out.

Warmth does not mean fewer weather disruptions

A warmer winter should not be mistaken for an uneventful one. The most prominent risks, however, differ between the two regions.

US: An active storm track shifts the risk toward flooding, ice, and snow

El Niño typically produces a more active storm track extending across the southern United States and toward the East Coast. This raises the potential for wetter-than-normal conditions and several forms of high-impact weather.

Flooding is one of the more credible hazards. A succession of storms crossing the southern United States could create repeated heavy-rainfall events, particularly in areas where soils are already saturated or otherwise vulnerable.

The same storm track also creates the ingredients for southern ice storms. Historical examples include significant icing events in December 2015 and January 2024. The limited historical record makes it difficult to predict an above-normal ice season with confidence, but the atmospheric setup creates clear vulnerability.

Major East Coast snowstorms are also possible. Strong El Niño winters have produced memorable snow events when abundant moisture and sufficiently cold air have arrived at the same time. The warmer background pattern may make those combinations less frequent, but it does not remove the potential for a high-impact storm.

The western water outlook is similarly mixed. Strong El Niño analogs provide reason for optimism in California, where several comparable winters produced exceptionally wet conditions and improved snowpack. Farther north, near- to below-normal snowpack remains more likely across the Pacific Northwest, meaning existing water-supply concerns may persist.

Europe: Brief cold reversals could still create significant disruption

The European outlook does not indicate the same broad storm-track risks highlighted for North America. Instead, one of the most consequential departures from the forecast would be a period of Arctic blocking that brings cold air into the region.

Even if the broader winter remains warm, a short cold outbreak could still increase heating demand and place pressure on energy systems, transport networks, and infrastructure. The impact of the winter may therefore depend not only on the seasonal average, but also on how quickly conditions change and how long colder patterns persist.

Short-lived shifts create decisive moments for business

The central signal for winter 2026–27 is persistent warmth across both North America and Europe. Yet seasonal conditions will still be punctuated by shorter-term patterns capable of producing cold outbreaks and major storms.

A warm seasonal forecast can help establish the baseline, but the greatest operational impacts may come from departures from it. In the United States, that could mean a short-lived cold outbreak, an ice storm in an exposed region, or a series of heavy-rainfall events along the southern storm track. In Europe, a period of Arctic blocking could quickly change heating demand and operating conditions, even if it does not alter the seasonal result.

Overall heating demand is likely to be lower across both regions. However, organizations will still need to monitor when and where episodic risks are developing. The difference between disruption and effective response may be determined during the shorter periods when the broader pattern temporarily breaks.

Winter 2026–27 may ultimately be remembered for its warmth on both sides of the Atlantic. Its most consequential moments, however, could still come from the exceptions.