Stronger Polar Vortex Could Bring Dynamic Conditions to Europe

Still high-pressure blocking patterns at first

Next week, there is an increasing risk for high pressure to move west of the U.K., so called Atlantic Ridge, abbreviated AtR regime. This should deliver a colder north-west or even northerly flows mainly downstream to the U.K. There is still low confidence for most of Great Britain. However, this pattern is likely affecting western, partly south-western and especially central-eastern Europe with colder, slightly wetter, and windier conditions. It should also turn wetter and cooler in parts of southern Europe/Italy.

 

The latter could evolve into a complicated high-over-low pattern. This means a high-pressure bridge roughly from the U.K. via northern parts of western-central to northern Europe and low pressure located more over central-southern Europe and into the central Mediterranean basin.

 

There is a risk of stronger low pressure developing over northern Italy with the likelihood of heavy, if not extreme, precipitation extending into the Adriatic Sea and western or southern Balkans. In contrast, there could be early snow in parts of central-eastern Europe (e.g. central and southern Germany) on the northern flank of the low pressure over northern Italy, accompanied by brisk north-easterly winds.

 

 

The stratospheric polar vortex will soon be stronger

The graph below shows the stratospheric polar vortex becoming stronger later in November continuing through early December.

What does it mean for the prevailing circulation patterns in the North Atlantic European sector?

The following graphic shows an impressive downward propagation of westerly wind momentum starting around 20 November, 2024.

 

 

“From mid-to-late November, a more active North Atlantic pattern could prevail, bringing wetter, windier weather to the northern half of Europe. ”

Therefore, during week 47 (18–24 November), a more active North Atlantic pattern (with a positive North Atlantic Oscillation/Arctic Oscillation index) could prevail bringing wetter, windier weather to the northern half of Europe, but mostly milder conditions across larger parts of Europe.

A few intense low-pressure systems that cross the U.K. and/or western Europe are possible, leading to stormy weather at times. However, there remains a risk of a negative NAO or sharper AtR regime, with a colder pattern in those parts or further east across continental Europe and/or Fennoscandia.

The milder, wetter, and windier conditions described above could set in at the end of November and continue through early December. Refer below to the latest DTN forecast charts for December.

 

 

The resulting weather patterns have significant implications across multiple sectors, most notably transportation and logistics companies and utilities balancing supply and demand.

For additional weather insights, watch our seasonal outlook webinar series.

 

About the author

Dr. Jens Bonewitz

Dr. Jens Bonewitz is an experienced long-range energy meteorologist at DTN. He consults with utility and renewable energy clients to help plan and prepare for the impact of weather. He combines research and its practical applications to produce meaningful weather forecasts within the S2S range.