Monday, November 9, 2026 Morning Edition Story Atlas Storylines Almanac Verification Desk Archive
Your skyForecast Points Subscribe
Forecast Post
Storyline · active · Season thread

Polar Vortex Watch 2026–27

Every dispatch on this road this season, in order: the thread a daily newsletter leaves behind when you read it end to end.

2Dispatches
3Days · OCT 26–OCT 28
I-10Stratosphere
Where the dispatches were filed2 of 2 placed
Map of North America and the Atlantic with a shield at each dispatch's place Natural Earth · places from the headlines
Eyes on stratosphere but any impacts down here will be weeks away if come to fruition FIGURE 1 OCT 28 · I-10 STRATOSPHERE Eyes on stratosphere but any impacts down here will be weeks away if come to fruition
The route · every exit
  1. Exit 1 · OCT 26 · Subscribers Potential stratospheric polar vortex breakdown in early November would be unprecedented Arctic stratosphere
  2. Exit 2 · OCT 28 Eyes on stratosphere but any impacts down here will be weeks away if come to fruition Arctic stratosphere
END Still active. The next dispatch adds an exit.

Why I-10?

Stratosphere stories ride Interstate 10, after the 10 hPa level where the polar vortex is measured, some 30 kilometres up.

Polar vortex

The band of strong westerly winds circling the Arctic in the stratosphere through the cold season.

Sudden stratospheric warming

A rapid rise in polar stratospheric temperature as the vortex weakens, splits or is displaced.

10 hPa

A pressure level about 30 km up, the standard height for measuring the vortex; the shield number of this road.