28/01/2026
A sudden stratospheric warming is fracturing the polar vortex 🚨
The stratosphere above the Arctic is heating up rapidly. Early February now carries strong signals of a sudden stratospheric warming (SSW) event — a rare atmospheric disturbance that may drive Arctic air deep into the mid-latitudes.
Normally, the polar vortex acts as a high-altitude barrier, spinning in a stable loop and keeping cold air locked near the poles. But when the stratosphere warms suddenly — often by more than 90 °F (50 °C) above normal — that circulation can collapse. The result is a broken vortex, split into smaller cores, and a release of polar air to regions far south of the Arctic Circle.
Forecasts show this process is already underway. Stratospheric winds are weakening. Pressure is rising over the polar region. And ensemble models from both the ECMWF and GFS show a likely breakdown of the vortex structure in early February. This disruption will likely displace cold air into eastern North America and parts of Europe.
Historically, SSW events have been linked to some of the coldest winter outbreaks on record. But their effects take time to reach the surface — often appearing 1 to 3 weeks later. Still, model guidance now shows a strong trend: colder-than-normal conditions spreading southward through mid-February.
This won’t guarantee record-breaking storms. But it does suggest a shift — from a contained Arctic, to one that’s spilling outward.
Learn more:
"Stratospheric Warming Alert: A Massive Shift in the Polar Vortex is Forecast for early February." Severe Weather Europe, 2026.