What is a sudden stratospheric warming event?

A sudden stratospheric warming (SSW) event is a dramatic warming in the polar stratosphere that can disrupt the polar vortex and influence weather patterns at the Earth's surface.

How could the La Niña weather pattern affect the upcoming winter?

The relationship between the polar vortex and the La Niña pattern is complex, and they will both play a role in shaping the winter weather. However, the behavior of the polar vortex is expected to be more influential in determining how cold it gets.

What are the potential impacts of an SSW event in November?

If an SSW event occurs in November, it would be a rare and extraordinary event. It could lead to an extended period of colder and snowier weather starting in December and lasting into early January, greatly increasing the odds of a harsher winter across the United States.

Home / Weather / Rare November Stratospheric Warming Event Threatens Winter Forecast

Rare November Stratospheric Warming Event Threatens Winter Forecast

15 Nov, 2025

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Summary

Sudden stratospheric warming event may occur, disrupting polar vortex
Relationship between polar vortex and La Niña pattern is complex
Potential for extended period of colder and snowier weather starting in December

According to the latest weather reports, a rare and potentially disruptive event may be on the horizon for the upcoming winter season. Meteorologists have detected signs of a sudden stratospheric warming (SSW) event, which could significantly impact the behavior of the polar vortex and the overall winter forecast.

The stratosphere above the North Pole is showing signs of a dramatic warming, which could push the cold air from the north towards the United States. This type of SSW event is considered the largest disruption to the polar vortex and has only been observed twice in November before the satellite era.

The relationship between the polar vortex and the ongoing La Niña weather pattern is complex, and there is no clear winner between the two. However, the behavior of the polar vortex is expected to be more influential in determining the severity of the cold weather. If the stratospheric warming strongly influences the jet stream, it could lead to an extended period of colder and snowier conditions starting in December and potentially lasting into early January.