Overview
- NOAA’s Space Weather Prediction Center issued a severe G4 storm watch for Nov. 12, following a G2 watch on Nov. 11 and a G3 watch for Nov. 13.
- Auroras were photographed across much of the United States, with sightings reported as far south as Alabama and Northern California, and the UK Met Office posted a rare G4 alert for parts of the UK.
- Two CMEs reached Earth late Nov. 11 and early Nov. 12, and a third, more energetic CME tied to an X5.1 flare was forecast to arrive around midday UTC on Nov. 12.
- Officials warned of temporary impacts to satellites, GPS and radio communications, and possible power‑grid voltage control issues during the strongest storm periods.
- Forecasters noted substantial timing uncertainty, saying upstream satellite detections typically provide only 15–60 minutes of lead time, with additional aurora chances expected into Wednesday night where skies are clear.