Polar Vortex disruption expected after January stratospheric warming
A Sudden Stratospheric Warming (SSW) event evolving over the Arctic through mid-January 2026 is forecast to weaken and displace the Polar Vortex, according to ECMWF and NOAA extended-range guidance. The disturbance is expected to propagate downward over the following weeks, raising the probability of Arctic air outbreaks and colder-than-normal conditions in parts of North America and Europe during the second half of January 2026.











