Stretched polar vortex and warm Arctic set up U.S. winter blast

Meteorologists say a stretched polar vortex, driven by warm Arctic waters, low sea ice and an unusually cold continental land mass, will steer a powerful winter storm into much of the United States later this week. Forecasts warn the system could deliver frigid temperatures, heavy snow and extensive ice from the central Plains through the East Coast, with impacts stretching into the Southeast.

Models show the system developing late in the week and moving through Friday into early next week, with snow beginning in parts of the South on Friday and winter weather reaching portions of the Southeast by Saturday. The National Weather Service short-range forecast predicts an Arctic air mass will bring “frigid sub-zero and single digit temperatures” to roughly two-thirds of the country by Sunday. Forecasters say significant icing could affect a swath from Texas to Delaware and that as many as 35 states may see hazardous winter conditions.

Scientists link the pattern to a combination of Arctic and continental influences. “The atmosphere is aligned perfectly that the pattern is locked into this warm Arctic, cold continent,” said Maue, describing how unusually warm Arctic waters and low sea ice are amplifying the jet stream’s distortion. Research scientists also point to heavy Siberian snowfall and seasonal shifts that have pushed and warped the normally circular polar vortex. “As far back as October 2025, changes in the Arctic and low sea ice were setting up conditions for the kind of stretched polar vortex,” said Judah Cohen, citing the extended timeline of Arctic anomalies that helped prime this pattern.

Forecasters warn the storm could leave many communities without heat or power. One meteorologist cautioned that “potentially hundreds of thousands of people may go without electricity and heat for days,” a prospect that raises immediate public health concerns. Extended outages and subzero temperatures increase the risk of hypothermia, carbon monoxide poisoning from unsafe indoor heating, and burst pipes that can disrupt water access and complicate care for people with chronic illnesses.

Low-income households, renters in poorly insulated housing, rural residents dependent on electric heat, and people experiencing homelessness face disproportionate risk. Hospitals and emergency services may be strained by storm-related injuries, carbon monoxide cases and the needs of patients who rely on electrically powered medical equipment. Public health officials and community organizations are likely to be pressed to coordinate warming centers, shelter capacity and targeted outreach to elderly and medically vulnerable residents.

Uncertainty remains about the storm’s precise track and which communities will see heavy snow versus mainly icing. Forecasters emphasize that model runs will continue to evolve through Friday, and that exact impacts will depend on the storm’s path and intensity. The cold pattern is expected to persist into early February, meaning accumulated snow and ice could take weeks to melt and extend secondary hazards.

Emergency managers, utilities and health systems are being urged to review contingency plans, ensure fuel supplies and ready warming centers, and communicate shelter and safety information to the public. Residents in the threatened areas are advised to monitor National Weather Service updates, heed local watches and warnings, and take steps to protect heat, water and medical needs in the days ahead.