An Arctic cold wave is moving across Europe as a persistent Greenland block redirects polar air southward. Forecast models show temperature anomalies between −10°C and −15°C (14°F and 5°F) at 850 hPa with extensive snow cover developing over much of the continent, with heavy snow already affecting parts of the UK and Balkans at the start of January 2026.
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.
A powerful winter storm named Johannes swept across the Nordic countries over the weekend, killing three people in Sweden and leaving hundreds of thousands without electricity across Sweden, Norway, and Finland. Sweden’s Meteorological and Hydrological Institute (SMHI) issued widespread alerts for strong winds as the system moved north. The storm, known as Hannes in Finland, also caused major travel disruptions, grounding flights and halting rail and ferry traffic.
Forecast models indicate that the Polar Vortex will strengthen in late December 2025 after a split and disrupted phase earlier in the season. The recovery is expected to influence North American and European weather in January 2026, potentially sending colder air southward while reorganizing jet stream flow.
A sudden stratospheric warming event has begun, deforming the Polar Vortex and setting the stage for a colder start to winter across the United States, Canada, and Europe.
A cold Arctic air mass is forecast to move into much of Europe between November 17 and 21, 2025, lowering temperatures several degrees below normal and producing a mix of hill snow and overnight ice.
An early-season stratospheric warming event is forecast to weaken the polar vortex in the coming weeks, potentially influencing winter 2025–26 weather across North America and Europe.
A deadly tornado struck the Val-d’Oise department, north-east of Paris, France, at around 17:45 LT (15:45 UTC) on October 20, 2025, killing one person and injuring nine, four critically. The violent, short-lived storm collapsed several construction cranes in Ermont, caused widespread roof damage, and uprooted trees across neighbouring municipalities.
At least 3 people have been reported dead due to the record-breaking Storm Amy that swept across Northern Europe through the weekend causing hundred of thousands of power outages in multiple countries including Ireland, the UK, France, and Norway. While restoration efforts continue thousands remain without power in the affected regions as of October 6, 2025.
Storm Amy is forecast to bring hurricane-force winds to Ireland and the UK on October 3, 2025, with Met Office amber warnings and Met Éireann red marine warnings in effect.
