The Arctic is warming more than three times faster than the global average. Sea ice has declined. Autumn snow cover across Siberia has increased.⁵
Judah Cohen and colleagues argued in Science in 2021 that this combination plausibly increases the probability of the wave patterns that weaken and displace the polar vortex.⁵ Their claim is not that warming causes individual outbreaks, but that it may tilt the background circulation toward disruption.
The Intergovernmental Panel on Climate Change is more cautious. Cold extremes have decreased overall, and attribution of mid-latitude cold outbreaks to Arctic amplification remains uncertain.⁶
Both statements can be true.
The atmosphere can warm and still produce damaging cold.
What matters most is not whether the vortex exists, but the environment in which its disruptions occur.
A warmer atmosphere holds more moisture. A weaker temperature gradient makes the jet stream more prone to large meanders. When cold outbreaks happen now, they occur in a system with more energy available for snowfall, ice loading, and infrastructure stress.⁶
This winter’s pattern was also nudged by the Pacific background.
NOAA reported in early January that La Niña conditions were weakening but still influencing the jet stream.⁷ By strengthening the subtropical jet and reinforcing the ridge–trough pattern over North America, La Niña likely helped sustain a circulation already predisposed to lock in place.
This is why forecasters did not promise a quick release.
There is no evidence this configuration will persist across many winters. The polar vortex weakens each spring and reforms each fall. Displacement events remain episodic.⁴
What persists is risk.
A climate with fewer cold days overall can still produce winters that fail abruptly. A grid designed around twentieth-century design temperatures and planning horizons may no longer be adequate for twenty-first-century extremes.
By February, temperatures will rise. Snow will melt. The vortex will recentralize.
The unresolved question this winter leaves behind is not whether Arctic air will come south again.
It is whether the systems we build next will assume the climate we used to have, or the one we now inhabit.
Bibliography
1. National Weather Service, January 2026 Storm Reports and Cooperative Observer Data Official snowfall and temperature measurements across Northeast and Great Lakes during January 21–24 storm sequence.
2. Reuters, January 23, 2026 Snow starts falling in Texas, Oklahoma as eastern US braces for winter storm Reporting on outages, ice damage, and emergency grid measures across Mid-South and Plains.
3. NOAA Climate Prediction Center, January 23, 2026 Week 3–4 Outlook Discussion Operational forecast diagnosing negative Arctic Oscillation and below-normal temperature probabilities for eastern US.